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Common cold



Related Terms
  • Acute viral nasopharyngitis, adenoviruses, adrenal gland, allergic rhinitis, allergy, antihistamine, benzocaine, bronchial tubes, bronchitis, cilia, coronaviruses, cortisol, coxsackieviruses, crystal meth, cytokines, dander, dyclonine, echoviruses, epithelial, eustachian tubes, Fahrenheit, flu, hay fever, hexylresorcinol, HIV, human immunodeficiency virus, humidifier, immune system, immunity, influenza, larynx, lozenges, malnutrition, menthol, methamphetamine, mucous membrane, mucus, otitis media, phenol/sodium phenolate, pneumonia, respiratory syncytial viruses (RSV), rhinoviruses, sinus, sinusitis, Strep throat, stress, symptomatic, thymus gland, trachea, turbinates, vaporizer, viral infection, viral load, virus.

Background
  • The common cold, or acute viral nasopharyngitis, is a viral infection of the upper respiratory system, which may involve the nose, throat, sinuses, eustachian tubes (connects the ears to the throat), trachea (windpipe), larynx (voice box), and bronchial tubes (airways).
  • Colds are one of the leading causes of doctor visits and missed days from school and work. According to the Centers for Disease Control and Prevention (CDC), 22 million school days are lost annually in the United States as a result of the common cold. Over the course of a year, people in the United States suffer one billion colds, according to some estimates.
  • Americans spend about $2.9 billion on over-the-counter (OTC) drugs in addition to $400 million on prescription medicines annually for the symptomatic relief from colds.
  • It is estimated that the average person contracts more than 50 colds during a lifetime. Anyone can get a cold, although pre-school and grade school children catch them more frequently than adolescents and adults.
  • One of the main reasons that colds are so common among children is because they are often in close contact with each other in daycare centers and schools. In families with children in school, the number of colds per child can be as high as twelve a year. Also, the thymus gland, which produces immune system cells, is immature in children. Subsequently they have decreased resistance to bacterial and viral infections such as colds.
  • Adults average about two to four colds annually, although the range varies widely. Women, especially those aged 20-30 years, experience more colds than men, possibly due to closer contact with children. Based on studies, on average, people older than 60 have less than one cold a year.
  • In the United States, most colds occur during the fall and winter. Beginning in late August or early September, the rate of colds increases slowly over a few weeks and remains high until March or April, when it declines. The seasonal variation may relate to the opening of schools and to cold weather, which prompt people to spend more time indoors and increase the chances that viruses will spread from person to person.
  • Seasonal changes in relative humidity also may affect the prevalence of colds. The most common cold-causing viruses survive better when humidity is low during the colder months of the year. Cold weather also may make the inside lining of the nose drier and more vulnerable to viral infection.

Risk factors and causes
  • The cause of developing a cold is due to a viral infection, including rhinoviruses, coronaviruses, adenoviruses, echoviruses, respiratory syncytial viruses (RSV), and coxsackieviruses, which can infect the upper respiratory system. Although over a hundred different viruses can cause colds, 30-50% are caused by rhinoviruses.
  • The nose contains shelf-like structures called turbinates, which help trap particles (dust, dander, dirt, and viruses) entering the nasal passages. Material deposited in the nose is transported by cilia, which are hair-like structures that sweep particles to the back of the throat within 10-15 minutes of exposure. Viruses attach to receptors on epithelial (outer layer of skin) cells. In response to infection, the immune system triggers a series of events, including release of inflammatory cytokines (a group of proteins that help regulate inflammation, blood cell production, and immunity), such as interleukin-6 (IL-6), interleukin-8 (IL-8), and granulocyte-macrophage colony-stimulating factor or GMCSF), fluid leakage (runny nose), mucous membrane swelling (stuffy nose), increased mucous production, and stimulation of sneeze and cough reflexes. Nasal symptoms can begin as early as two hours after exposure, while cough and sore throat symptoms usually begin 10-12 hours following exposure to the virus. In the early stages of a cold, when the number of infecting viruses is still low, it may be possible for the body to build an effective immune response that prevents the cold from worsening. Keeping the number of viruses, called viral load, low decreases the ability of the cold virus to replicate (multiply) and cause infection.
  • The most common means of infection is from direct contact with the cold virus, such as an individual touching their skin to environmental surfaces (including telephones, computer keyboards, and stair rails) that have cold germs on them and then touching the eyes or nose. If an individual is physically exhausted or overtired, the chances of becoming a victim to the cold virus increase due to a impairment in immunity, or the decreased ability of the immune system to fight off infection.
  • Colds are also easily transmitted (by coughing or sneezing) by inhaling droplets of mucus contaminated with cold viruses. Mucus is a thick, slippery secretion of the inner lining or organs (called mucous membranes) in the body including the nostril, ears, anus, and lips. The cold virus is spread when the infected mucus drops come in contact with other individual's noses and eyes, occurring this way more frequently than through the mouth.
  • Social activity: Individuals exposed to large amounts of people during the day are also exposed to many viruses. Children attending school or playing with other kids, traveling in airplanes or buses, and having large families increases the risk of exposure to a cold virus. Being around people that are sneezing and coughing increases the chances for getting a cold virus. Touching things that others frequently touch, such as railings and doors in public facilities, also increases the chances of developing a cold. An individual's work place may also increase their chances of exposure to a cold virus. Healthcare workers (such as nurses, pharmacists, and doctors), day care workers, people that work in retail stores, and individuals in public office are exposed to many people daily, where the chances of viral exposure and developing a cold is increased.
  • Age: Children and infants (less than 14 years of age) are especially susceptible to colds. Their immune systems have not yet become adjusted to being exposed to various cold viruses and have not yet developed resistance to the viruses commonly encountered. Children also may not be as careful about cleanliness such as hand washing. Children tend to spend lots of time with other children (at play and school), making it easy for colds to spread. As they age, immunity develops for many of the common viruses that cause colds. Colds will generally occur less frequently with age.
  • Seasonal changes: Both children and adults seem to be most susceptible to colds in fall and winter. In cold months when the air is very dry, people turn on their heating systems, drying the air even more. Dry air dehydrates the mucous membranes in the nose and throat, which are the first line of defense against the viruses. This allows the viruses to attack the tissue in the nose and throat. Individuals working in air conditioned offices tend to have more summer colds than people who do not work in air conditioned environments. Air conditioning dries out the air and the mucous membranes and can circulate viruses in the air.
  • Environmental toxins: The risk of respiratory infections is increased by exposure to environmental toxins, including cigarette smoke, which can injure airways and damage the cilia (tiny hair-like structures that help keep the airways clear). Physically engaging in smoking or breathing in passive (second hand) smoke can damage the cilia. Toxic fumes, industrial smoke, and other air pollutants are also environmental risk factors.
  • Lowered immunity: Individuals with lowered immunity, such as those with the human immunodeficiency virus (HIV) or cancer, and individuals taking certain medications such as chemotherapy, are at greater risk of developing colds. Colds can be severe in these individuals, due to poor immune status.
  • Medications: Drug therapies, including corticosteroid (steroid) treatments, chemotherapy, or other medications that suppress the immune system also increase the risk of developing an infection from a cold virus.
  • Stress: Stress can lower the resistance to infection by depressing the immune system Stress causes the adrenal glands to increase the production of the stress hormone called cortisol. During normal stressful circumstances, cortisol production is a healthy response of the body. Chronic (long-term) stress, however, causes the levels of cortisol to stay increased, leading to decreased immunity, hyperinsulinemia (the inability of the body to process insulin), and an increase in blood pressure. Stress during menopause may also increase the chances of catching a cold due to impaired immunity.
  • Too much exercise: High-intensity or endurance exercises appear to suppress the immune system while they are being performed. Some highly trained athletes, for instance, report being susceptible to colds after strenuous exercise.
  • Malnutrition: Low vitamin and mineral levels, such as vitamins A, E, C, the B vitamins, selenium, and zinc, may decrease immunity and increase the chances of getting a cold. Very low fat diets also appear to lower the immune system.
  • Lack of sleep: Sleep helps the body recharge. Proper sleep (eight hours of uninterrupted sleep for an adult) can help keep the body's immune system healthy and fight off colds.

Signs and symptoms
  • Symptoms of a common cold usually appear about one to three days after exposure to a cold virus. Signs and symptoms of a common cold may include runny or stuffy nose, itchy or sore throat, dry cough, facial pressure due to sinuses (hollow bones in the front of the face), slight body aches or a mild headache, sneezing, itchy, watery eyes, low-grade fever (less than 102 degrees Fahrenheit), and mild fatigue (tiredness).
  • Nasal discharge may become thicker as a common cold runs its course. What makes a cold different from other viral infections (such as influenza) is that the individual generally will not have a high fever or colored sputum. They are also unlikely to experience significant fatigue from a common cold.
  • Colds last on average for one week. Mild colds may last only two or three days while severe colds may last for up to two weeks. Cough due to a cold can last for hours or days.

Diagnosis
  • Colds are usually diagnosed clinically by the presence of typical symptoms including runny or stuffy nose, itchy or sore throat, dry cough, nasal congestion, facial pressure (sinuses), slight body aches or a mild headache, sneezing, itchy, watery eyes, low-grade fever (less than 102 degrees Fahrenheit), and mild fatigue (tiredness).
  • If the symptoms worsen after one to two weeks, a doctor will examine the individual's head, neck, and lungs, for signs and symptoms of more serious respiratory illnesses, such as pneumonia or bronchitis.
  • Upon presentation, a doctor may perform a throat culture or blood test to rule out infections secondary to bacteria such as Streptococcus (Strep throat).
  • Often confused with influenza, the common cold is caused by different types of viruses and usually does not result in a significantly higher body temperature. A high fever (above 102 degrees Fahrenheit) is a very reliable indicator of the flu. Hay fever may also cause many of the same symptoms as a cold, including runny or stuffy nose, cough, and scratchy throat.
  • Allergies to dander, dust, molds, or pollens (allergic rhinitis or hay fever) also can cause a runny nose, although this usually induces symptoms more persistent than the common cold,

Complications
  • Bacterial infections: Colds can occasionally lead to bacterial infections of the middle ear, throat, or sinuses, requiring treatment with antibiotics. High fever (greater than 102 degrees Fahrenheit), significantly swollen glands, severe sinus pain, and a cough that produces colored mucus, may indicate a complication or more serious illness requiring a visit to a doctor. Colds also can produce colored mucus, and a doctor will have to determine if the mucus is infected from a cold virus or another infection, such as influenza or bacteria. Samples of the mucus are taken and studied under a microscope to determine the exact cause of the infection.
  • Sinusitis: Between 0.5% and five percent of people with colds develop sinusitis, an infection in the sinus cavities (air-filled spaces in the front of the skull), including pressure, nasal stuffiness, and headache. Sinusitis is usually mild, but if it becomes severe, antibiotics generally eliminate further problems. In rare cases, however, sinusitis can be serious.
  • Bronchitis and pneumonia: The common cold poses a risk for bronchitis and pneumonia in nursing home patients and other people who may be susceptible to infection. Some experts believe that the rhinovirus may play a more significant role than the flu in causing lower respiratory infections in such individuals.
  • Wheezing: Rhinovirus infection often triggers asthma attacks in individuals with asthma.
  • Acute ear infection (otitis media): The most frequent complication of common colds in children is otitis media, or an ear infection in which bacteria infect the space behind the eardrum. Typical signs and symptoms of otitis media include earaches and, in some cases, green or yellow discharge from the nose, or the return of a fever following a common cold. Children who are too young to verbalize their distress may simply cry or pull on the affected ear.

Treatment
  • There is no cure for the common cold. Over-the-counter (OTC) cold preparations may be used for symptoms.
  • Healthcare professionals recommend seeking medical attention if a patient has a fever of 102 degrees Fahrenheit or higher, the fever is accompanied by aches, extreme fatigue, sweating, chills, and a cough with colored phlegm, or symptoms get worse instead of better or last more than 10 days. These are symptoms of a more serious viral illness such as influenza.
  • With a child that has a cold, medical attention is recommended if symptoms include a fever of 102 degrees Fahrenheit or higher with chills or sweating, a fever that lasts more than 72 hours, vomiting or abdominal pain, unusual sleepiness, severe headache, difficulty breathing, persistent crying, ear pain, or a persistent cough.
  • Pharmacological therapy:
  • Pain relievers and fever reducers: For fever, sore throat, body aches, and headache, acetaminophen (Tylenol®) or ibuprofen (Advil®, Motrin®) may be used over-the-counter. Acetaminophen can cause liver damage, especially if taken chronically, or in doses that exceed four grams daily. Healthcare professionals recommend carefully following dosing guidelines when giving acetaminophen to children, as dosing can be confusing. Also, it is recommended to never give aspirin to children ages three to 12. Aspirin may play a role in causing Reye's syndrome, a rare but potentially fatal illness in children.
  • Nasal decongestants: Nasal decongestants are useful medications for the common cold. Nasal decongestants help dilate (open) swollen mucous membranes of the nasal passages so the individual can breathe easier. Nasal decongestants include tablets, sprays, inhalers, and nose drops. Nasal decongestants include the oral decongestant pseudoephedrine (Sudafed®), nasal sprays oxymetolazone (Afrin®) and phenylephrine (Neo-Synephrine®), and the nasal inhalers propylhexedrine (Benzedrex®) or levmetamfetamine (Vicks Vapor Inhaler®). They are safe for most patients, but they do have many side effects and conditions in which they should not be used, including in people with heart disease, high blood pressure, thyroid disease, glaucoma (increased pressure in the eyes), diabetes, seizure disorders, enlarged prostate, or by individuals using a monoamine oxidase inhibitor (MAOI, type of antidepressant). Stinging, burning, sneezing, increased nasal discharge, drying of the nostrils, and altered taste may occur. If these effects continue or become bothersome, inform a doctor. Other side effects include rapid or pounding heartbeat, dizziness, trouble sleeping, shaking of the hands, and tremors. Healthcare professionals recommend not using decongestants while pregnant or breastfeeding. If symptoms get worse, a doctor may need to evaluate the situation.
  • Over time, decongestant nose drops, inhalers, and sprays can actually cause rebound congestion, which means the nasal passages are not able to function normally without using these medications. Prolonged use can also cause chronic inflammation of the mucous membranes. Decongestant nasal drops and sprays are not used for more than three days, which helps to stop the potential of nasal rebound.
  • There is widespread national abuse of pseudoephedrine tablets as a drug to make methamphetamine (crystal meth or meth), an illegal drug. Methamphetamine is a highly addictive, synthetically produced central nervous system stimulant with effects similar to cocaine. Meth is the most prevalent synthetic drug manufactured in the United States and is easily produced in home laboratories using common store-bought chemicals. The ease of manufacturing meth and its highly addictive potential has caused the use of the drug to increase throughout the nation. Its use has reached epidemic levels in many parts of the country. National and state laws have attempted to stem this criminal activity by establishing limits on sales of pseudoephedrine. The pharmacist or pharmacy representative may ask for a name and address in many states to prove that the pseudoephedrine is purchased legitimately as a decongestant. There may also be limits on the how much psuedoephedrine can be purchased in one transaction as well as over a certain time period. Psuedoephedrine products may not be available in all states over-the-counter (OTC), and may need to be purchased from behind the pharmacy counter. Also, a new oral nasal decongestant formulation (Sudafed PE®) is available that decreases the potential for abuse. Sudafed PE® contains the nasal decongestant phenylephrine and not pseudoephedrine.
  • Antihistamines: Antihistamines dry up excess nasal secretions (mucus), and in this way help to temporarily stop a runny nose. But they can also cause side effects such as dry mouth, constipation, and drowsiness as well as confusion and increased risk of falls if administered to elderly patients. Non-sedating antihistamines include fexofenadine (Allegra® and cetirizine (Zyrtec®.) Antihistamines that cause sedation include diphenhydramine (Benadryl®), clemastine (Tavist®), chlorpheniramine (Chlor-Trimeton®), and brompheniramine (Dimetane®.)
  • Cough syrups: Nonprescription cough syrups, containing various combinations of antihistamines, decongestants, and cough suppressants, are available over-the-counter (OTC) for symptomatic relief of cough associated with a cold. Many doctors strongly discourage the use of these combination medications for any child younger than age two, in whom accidental overdoses could be fatal. Coughs associated with a cold usually last less than two to three weeks. If a cough lasts longer than three weeks, see a doctor. Cough due to colds in adults may be safely treated for as long as seven days. If the cough is productive (brings up mucus), the ingredient guaifenesin can help break up the chest congestion (water intake is also important.) If the cough is dry and hacking, a cough suppressant (dextromethorphan) can stop the cough.
  • Lozenges: Sore throat caused by a cold may be self-treated if the pain is minor. Experts recommend not self-treating sore throat for more than two days. If a sore throat lasts more than seven days, healthcare professionals recommend seeing a doctor. Lozenges for sore throat contain active ingredients such as the anesthetics benzocaine, menthol, dyclonine, phenol/sodium phenolate, and hexylresorcinol. Phenol/sodium phenolate and hexylresorcinol also have antibacterial properties.
  • Antiviral: A few studies have investigated the use of antiviral medications to treat rhinovirus, including interferon alfa-2a and interferon gamma. These drugs are expensive and have to be refrigerated and injected. The most common side effect of interferon alfa-2a or alfa-2b therapy is a flu-like reaction with fever, fatigue, irritability, chills, headaches, and muscle aches. These effects should become less severe and less frequent as therapy progresses.
  • Pleconaril (Picovir®) is an anti-viral drug in clinical testing that targets picornaviruses, the viruses that cause the majority of common colds such as rhinoviruses. Pleconaril has been reported to be effective in an oral form, but it causes severe adverse effects including liver and kidney failure. An intranasal form with less side effects is currently under development.
  • Antibiotics: Healthcare professionals do not recommend using antibiotics to treat a cold. Antibiotic resistance has been called one of the world's most pressing public health problems. It is caused by the over prescribing of antibiotics for conditions that will not respond to antibiotics, such as outer ear infections and viral infections, including colds and influenza.
  • Others: Ipratropium bromide (Atrovent®), a prescription nasal spray, significantly reduced nasal drainage and sneezing in studies of naturally occurring colds.The main side effects included nasaldryness, occasional epistaxis (nosebleeds), and headache. The duration of relieffrom nasal stuffiness is thought to be over threehours. Nedocromil (Tilade®) and sodium cromoglycate (Cromolyn®) are prescription drugs used in the nose have been reported to reduce the severity of the rhinovirus upper respiratory tractinfections (a common cold).
  • Non-pharmacological therapy:
  • Non drug therapy can help reduce cold symptoms and is recommended by healthcare professionals for all infants younger than nine months. Patients of all ages benefit from rest and increased intake of fluids. The American Academy of Pediatrics highly recommends the use of calibrated measuring devices for the administration of all liquid medications to children and infants.
  • Saline nasal drops:Isotonic saline nasal drops are recommended for infants. Healthcare professionals recommend one to two drops in each nostril 15 to 20 minutes before feeding and bedtime and repeated ten minutes later. Adults and children may also use saline nasal drops (Ocean® nasal spray) to relieve dry and inflamed nasal passages.
  • Nasal bulb aspirator: A nasal bulb aspirator may be used to gently suction mucus and aid in clearing the nasal passages in infants and young children. Nasal bulb aspirators use gentle suction to remove excess mucus from the nasal passages. They can be purchased without a prescription at pharmacies and most retail outlets.
  • Elevating the head: Elevating the head of an infant's or child's bed may facilitate the drainage of secretions. Parents and caregivers should be cautioned, however, never to place pillows around or under an infant's head due to increased risk of suffocation.
  • Humidification: A cool mist vaporizer will add moisture to the air, relieving symptoms such as sore throat and congestion. Hot steam humidifiers are not recommended because of the risk of scalding. Humidifiers and vaporizers must be cleaned frequently to deter growth of bacteria and other pathogens. Infants and young children also benefit from exposure to warm, steamy air, which helps to clear nasal and bronchial passages of mucus and to ease breathing, especially at night. Parents can hold the infant or child on their lap outside the shower while running a warm or hot shower to generate steam. The child should not be placed in the water.
  • Petroleum jelly: Petroleum jelly may be applied on skin underneath the nose if it becomes raw from repeated wiping.

Integrative therapies
  • Strong scientific evidence:
  • Andrographis: Andrographis (Andrographispaniculata) has been widely used in Indian (Hindu) folk medicine and Ayurvedic forms of medicine. A combination of andrographis with Siberian ginseng or eleuthero (Eleutherococcus senticosus) called Kan Jang® may be effective for upper respiratory tract infection treatment. In clinical study, this treatment was given for five days, and was shown to improve fever, muscle soreness, cough, sore throat, and headache.
  • Several cases of anaphylactic reactions, including shock, have been reported to the World Health Organization Collaborating Center for International Drug Monitoring as of June 2003. Avoid with infertility or patients actively trying to conceive. Use cautiously with diabetes, bleeding disorders, or high or low blood pressure or medications used for these conditions. Avoid if pregnant or breastfeeding.
  • Good scientific evidence:
  • Echinacea: Preliminary studies suggest that echinacea may not be helpful for prevention of upper respiratory tract infections in adults and children or treatment of upper respiratory tract infections in adults. Study results are conflicting and further research is needed to make a conclusion in this area.
  • Avoid if allergic to echinacea, its constituents, or any members of the Asteraceae/Compositae family (ragweed, chrysanthemums, marigolds, daisies). Use cautiously in patients prone to atopic reactions and in those with hemochromatosis and diabetes. Some natural medicine experts discourage the use of echinacea by people with conditions affecting the immune system, such as HIV/AIDS, some types of cancer, multiple sclerosis, tuberculosis, and rheumatologic diseases (such as rheumatoid arthritis or lupus). Use parenteral preparations of echinacea(no longer approved for use in Germany) cautiously. Use tinctures cautiously with alcoholic patients or in patients taking disulfiram or metronidazole. Avoid in patients presenting for anesthesia. Use cautiously if pregnant or breastfeeding.
  • Sage: Sage mouthwashes and gargles have been approved for use against sore throat in Germany by the German Commission E. Additional study is needed comparing sage to standard therapies for acute pharyngitis (inflammation of the pharnyx).
  • Avoid if allergic or hypersensitive to sage, its constituents, or to members of the Lamiaceae family. Use cautiously with hypertension (high blood pressure). Use the essential oil or tinctures cautiously in patients with epilepsy. Avoid with previous anaphylactic reactions to sage species, their constituents, or to members of the Lamiaceae family. Avoid if pregnant or breastfeeding.
  • Vitamin C: Vitamin C, or ascorbic acid, is a water-soluble vitamin, which is necessary in the body to form collagen in bones, cartilage, muscle, and blood vessels, and aids in the absorption of iron. Dietary sources of vitamin C include fruits and vegetables, particularly citrus fruits, such as oranges. Scientific studies generally suggest that vitamin C does not prevent the onset of cold symptoms. However, in a subset of studies in people living in extreme circumstances, including soldiers in sub-arctic exercises, skiers, and marathon runners, significant reductions in the risk of developing colds by approximately 50% have been reported. Additional study is needed to better determine the effectiveness of vitamin C for common cold prevention in extreme environments.
  • Avoid if allergic or sensitive to vitamin C product ingredients. Vitamin C is generally considered safe in amounts found in foods. Vitamin C supplements are also generally considered safe in most individuals if taken in recommended doses. Large doses (greater than 2 grams) may cause diarrhea and gastrointestinal upset. Avoid high doses of vitamin C with glucose 6-phosphate dehydrogenase deficiency, kidney disorders or stones, cirrhosis (inflammation of the liver), gout, or paroxysmal nocturnal hemoglobinuria (bleeding disorder). Vitamin C intake from food is generally considered safe if pregnant or breastfeeding. It is not clear if vitamin C supplements in doses higher than Dietary Reference Intake recommendations are safe for pregnant or breastfeeding women. Vitamin C is naturally found in breast milk.
  • Unclear or conflicting scientific evidence:
  • Andrographis: Based on clinical evidence, andrographis may be effective for upper respiratory tract infection prevention. Additional high-quality clinical study is needed to reach a conclusion.
  • Several cases of anaphylactic reactions, including shock, have been reported to the World Health Organization Collaborating Center for International Drug Monitoring as of June 2003. Avoid with infertility or patients actively trying to conceive. Use cautiously with diabetes, bleeding disorders, or high or low blood pressure or medications used for these conditions. Avoid if pregnant or breastfeeding.
  • Arginine: Early study suggests that arginine supplements may decrease the risk of respiratory infections. Large, well-controlled studies are needed to clarify this relationship.
  • Avoid if allergic to arginine, with a history of stroke, or liver or kidney disease. Avoid if pregnant or breastfeeding. Use caution if taking blood-thinning drugs (like warfarin or Coumadin®) and blood pressure drugs or herbs or supplements with similar effects. Blood potassium levels should be monitored. L-arginine may worsen symptoms of sickle cell disease. Caution is advised in patients taking prescription drugs to control blood sugar levels.
  • Astragalus: Astragalus is often used in Chinese medicine as a part of herbal mixtures to prevent or treat upper respiratory tract infections. Due to a lack of well-designed research, firm conclusions cannot be drawn at this time.
  • Avoid if allergic to astragalus, peas, or any related plants or with a history of Quillaja bark-induced asthma. Avoid with aspirin or aspirin products or herbs or supplements with similar effects. Avoid with inflammation (swelling) or fever, stroke, transplants, or autoimmune diseases (like HIV/AIDS). Stop use two weeks before surgery/dental/diagnostic procedures with a risk of bleeding and avoid use immediately after these procedures. Use cautiously with bleeding disorders, diabetes, high blood pressure, lipid disorders, or kidney disorders. Use cautiously with blood-thinners, blood sugar drugs, or diuretics or herbs and supplements with similar effects. Avoid if pregnant or breastfeeding.
  • Boneset: Boneset (Eupatorium perfoliatum) is native to eastern North America and was used by Native Americans to treat fevers. Boneset is used homeopathically in very dilute amounts for colds. Homeopathic boneset was found in limited available study to decrease the symptoms associated with a cold. Homeopathic medicines do not have side effects due to the very small amount of substance, such as boneset, used in their preparation.
  • Avoid if allergic or hypersensitive to boneset (Eupatorium perfoliatum), any of its constituents, or related members of the Asteraceae/Compositae family such as dandelion, goldenrod, ragweed, sunflower, and daisies. Use cautiously in small children, elderly individuals, or individuals suffering from a chronic condition. Use cautiously even in the amounts recommended by manufacturers, as boneset may promote sweating, the production of urine, and catharsis. Avoid with known liver or kidney conditions and in patients who ingest moderate to large amounts of alcohol. Avoid if pregnant or breastfeeding.
  • Bovine colostrum: Bovine colostrum has shown potential for immune stimulation. However, early evidence has not shown any benefit for reducing upper respiratory tract infection duration, although bovine colostrum may reduce symptoms. Further studies are required before a conclusion can be made.
  • Avoid if allergic to dairy products. Use cautiously because toxic compounds, such as polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethane (DDT), and dichlordiphenyldichloroethylene (DDE), have been found in human colostrum and breast milk. Thus, it is possible that these agents may be found in bovine colostrum. Avoid with, or if at risk for, cancer. Use cautiously with immune system disorders or atherosclerosis (hardening of the arteries). Use cautiously if taking medications, such as anti-diarrheal agents (e.g. Imodium®), insulin, or CNS agents (such as amphetamines, caffeine).
  • Chamomile: Chamomile (Matricaria recutita) has been used medicinally for thousands of years, and is widely used in Europe. It is a popular treatment for numerous ailments, including sleep disorders, anxiety, and digestion/intestinal conditions. In early study, inhalation of steam with chamomile extract was reported to help relieve symptoms of the common cold. Further research is needed to confirm these results. Caution is advised when taking chamomile supplements, as adverse effects including drowsiness are possible.
  • Avoid if allergic to chamomile. Anaphylaxis, throat swelling, skin allergic reactions and shortness of breath have been reported. Chamomile eyewash may cause allergic conjunctivitis (pinkeye). Stop use two weeks before surgery/dental/diagnostic procedures with bleeding risk, and do not use immediately after these procedures. Use cautiously if driving or operating machinery. Avoid if pregnant or breastfeeding.
  • Chiropractic: There is currently not enough reliable scientific evidence to conclude the effects of chiropractic techniques for respiratory tract infections. Additional study is needed in this area.
  • Avoid with vertebrobasilar vascular insufficiency, aneurysms, arteritis (inflammation of the arteries), or unstable spondylolisthesis (a slippage of the vertebrae in the spine). Avoid use on post-surgical areas of para-spinal tissue. Use cautiously with acute arthritis, brittle bone disease, conditions that cause decreased bone mineralization, bleeding disorders, migraines, or if at risk of tumors or metastasis of the spine. Use extra caution during cervical adjustments.
  • Elderberry and elder flower: Elder (Sambucus nigra) has been reported to have antiviral and antibacterial activity in laboratory studies. There is a small amount of research on the combination herbal product Sinupret®, which is a German product that contains elder and several other herbs in patients with bronchitis. This formula contains elder flowers (Sambucus nigra) as well as gentian root, verbena, cowslip flower, and sorrel. Although benefits have been suggested, due to design problems with this research, no clear conclusion can be drawn either for Sinupret® or elder in the management of bronchitis. Sinupret® has also been reported to have beneficial effects when used with antibiotics to treat sinus infections, although the majority of this evidence is not high quality and requires confirmation with better research.
  • Cyanide toxicity is possible with consumption of elder. Avoid if allergic to elder or to plants related to honeysuckle. Some reports exist of allergies from contact with fresh elder stems. Use caution with diabetes, high blood pressure or urinary problems, or with drugs used for any of these conditions. Use caution with anti-inflammatory agents, diuretics ("water pills" for high blood pressure), or laxatives. Avoid if pregnant or breastfeeding.
  • Euphorbia: Limited available clinical study involving senior patients with chronic bronchitis showed a significant effect of Euphorbia helioscopia. Larger trials are needed to evaluate the effect of Euphorbia helioscopia in a wider range of patients.
  • Avoid if allergic or hypersensitive to pollen from Euphorbia fulgens. Use cautiously with history of Epstein Barr virus infection or stomach conditions. Avoid if pregnant or breastfeeding.
  • Evening primrose oil: There is evidence that primrose oil, in combination with thyme, may have some benefits in the treatment of acute bronchitis. However, it is unclear if primrose alone is useful in treating bronchitis. More studies are needed to examine the effectiveness of primrose oil alone as a therapy for bronchitis.
  • Avoid if allergic to plants in the Onagraceae family (willow's herb, enchanter's nightshade) or gamma-linolenic acid. Avoid with seizure disorders. Use cautiously with drugs used for mental illness. Stop use two weeks before surgery with anesthesia. Avoid if pregnant or breastfeeding.
  • Garlic: Garlic (Allium sativum) may improve the immune system's ability to fight off infection, such as a cold virus, and may reduce the severity of upper respiratory tract infections. However, this has not been demonstrated in well-designed human studies.
  • Caution is advised when taking garlic supplements, as adverse effects including an increase in bleeding and drug interactions are possible. Garlic supplements should not be used if pregnant or breastfeeding, unless otherwise directed by a doctor.
  • Ginseng: Ginseng (CVT-E002) may be effective for preventing respiratory infections caused by the respiratory syncytial virus. More study is needed in this area.
  • Caution is advised when taking ginseng supplements, as numerous adverse effects including an increased risk of drug interactions are possible. Ginseng should not be used if pregnant or breastfeeding, unless otherwise directed by a doctor.
  • Goldenseal: Goldenseal (Hydrastis canadensis) has become a popular treatment for the common cold and upper respiratory tract infections, and is often added to Echinacea in commercial herbal cold remedies. Animal and laboratory research suggests that the goldenseal component berberine has effects against bacteria and inflammation. However, due to the very small amount of berberine in most goldenseal preparations, it is unclear whether goldenseal contains enough berberine to have the same effects.
  • Caution is advised when taking goldenseal supplements, as adverse effects including drug interactions are possible. Goldenseal supplements should not be used if pregnant or breastfeeding, unless otherwise directed by a doctor.
  • Green tea: Green tea is made from the dried leaves of Camellia sinensis, a perennial evergreen shrub. Green tea has a long history of use, dating back to China approximately 5,000 years ago. In humans, preliminary data suggests that a specific formulation of green tea may be effective for common cold prevention. Further well-designed clinical trials are needed to confirm these results.
  • Avoid if allergic or hypersensitive to caffeine or tannins. Use cautiously with diabetes or liver disease. Caution is advised when taking green tea supplements, as adverse effects including drug interactions are possible. Green tea supplements should not be used if pregnant or breast feeding unless otherwise directed by a doctor.
  • Guided imagery: Therapeutic guided imagery may be used to help patients relax and focus on images associated with personal issues they are confronting. Experienced guided imagery practitioners may use an interactive, objective guiding style to encourage patients to find solutions to problems by exploring their existing inner resources. Biofeedback is sometimes used with imagery to enhance meditative relaxation. Interactive guided imagery groups, classes, workshops, and seminars are available, as well as books and audiotapes. Preliminary research in children suggests that stress management and relaxation with guided imagery may reduce the duration of symptoms due to upper respiratory tract infections, including colds. Additional research is needed to confirm these results.
  • Guided imagery is usually intended to supplement medical care, not to replace it, and guided imagery should not be relied on as the sole therapy for a medical problem. Contact a qualified health care provider if mental or physical health is unstable or fragile. Never use guided imagery techniques while driving or doing any other activity that requires strict attention. Use cautiously with physical symptoms that can be brought about by stress, anxiety, or emotional upset because imagery may trigger these symptoms. If feeling unusually anxious while practicing guided imagery, or with a history of trauma or abuse, speak with a qualified healthcare provider before practicing guided imagery.
  • Horseradish: Horseradish may have antibiotic activity, and has been used in combination with other herbs to treat bronchitis. However, additional studies are needed that use horseradish as a single therapy before a conclusion can be made.
  • Avoid if allergic or hypersensitive to horseradish (Armoracia rusticana), its constituents, or members of the Brassicaceae family. Large oral doses may provoke allergic reactions. Use cautiously with clotting disorders, hypotension (low blood pressure), thyroid disorders, kidney disorders, kidney inflammation, gastrointestinal conditions, ulcers, and stomach ulcers. Use cautiously if taking anticoagulants or antiplatelets (blood thinning agents), antihypertensives (blood pressure-lowering agents), anti-inflammatory agents, or thyroid hormones. Use cautiously if undergoing treatment for cancer. Avoid medicinal amounts of horseradish if pregnant or breastfeeding, as glucosinolates from horseradish are considered a toxin that can be excreted through breast milk and may pose a toxicity hazard. Also, based on herbal textbooks and folkloric precedent, horseradish has been used to induce abortion.
  • Hydrotherapy: Hydrotherapy is broadly defined as the external application of water in any form or temperature (hot, cold, steam, liquid, ice) for healing purposes. It may include immersion in a bath or body of water (such as the ocean or a pool), use of water jets, douches, application of wet towels to the skin, or water birth. These approaches have been used for the relief of various diseases and injuries, or for general well being. There is preliminary evidence that daily showers with warm water followed by cold water, or cold water alone, may reduce the duration and frequency of common cold symptoms. Additional research is needed in this area before a clear conclusion can be drawn.
  • Avoid sudden or prolonged exposure to extreme temperatures in baths, wraps, saunas, or other forms of hydrotherapy, particularly with heart disease, lung disease, or if pregnant. Avoid with implanted medical devices, such as pacemakers, defibrillators, or liver infusion pumps. Vigorous use of water jets should be avoided with fractures, known blood clots, bleeding disorders, severe osteoporosis, open wounds, or during pregnancy. Use cautiously with Raynaud's disease, chilblains, acrocyanosis, erythrocyanosis, or impaired temperature sensitivity, such as neuropathy. Use cautiously if pregnant or breastfeeding. Hydrotherapy should not delay the time to diagnosis or treatment with more proven techniques or therapies, and it should not be used as the sole approach to illnesses. Patients with known illnesses should consult their physicians before starting hydrotherapy.
  • Licorice: Historically, licorice has been used for its expectorant and anti-tussive effects. The herbal combination product, KanJang®, has been studied for the treatment of uncomplicated upper respiratory tract infections. Results are mixed, and additional study is needed.
  • Avoid licorice with a known allergy to licorice, any component of licorice, or any member of the Fabaceae (Leguminosae) plant family. Avoid licorice with congestive heart failure, coronary heart disease, kidney or liver disease, fluid retention, high blood pressure, hormonal abnormalities or if taking diuretics. Licorice can cause abnormally low testosterone levels in men or high prolactin or estrogen levels in women. This may make it difficult to become pregnant and may cause menstrual abnormalities.
  • Moxibustion: Moxibustion is the application of heat to variouspoints on the body. It is widely used traditionally in China for treatment of upper respiratory tract infections in children. However, at this time evidence is insufficient.
  • Use cautiously over large blood vessels and thin or weak skin. Avoid with aneurysms, any kind of "heat syndrome," cardiac disease, convulsions or cramps, diabetic neuropathy, extreme fatigue and/or anemia, fever, inflammatory conditions, over allergic skin conditions or ulcerated sores, or skin adhesions. Avoid if pregnant or breastfeeding. Avoid areas with an inflamed organ, contraindicated acupuncture points, the face, genitals, head, inflamed areas in general, nipples, and skin adhesions. Avoid in patients who have just finished exercising or taking a hot bath or shower. Use cautiously with elderly people with large vessels. It is considered not advisable to bathe or shower for up to 24 hours after a moxibustion treatment.
  • Nasal irrigation: The three forms of nasal irrigation therapies used in clinical trials have been saline lavage, which uses a warm liquid solution of salt water; humidified warm air lavage (in hyperthermia or low body temperature); and large-particle nebulized aerosol therapy, which uses an aerosolized (droplets spread in the air) saline solution. Occasionally, antibiotics are added to the solution. Nasal saline irrigation is still the main treatment for acute rhinitis (runny nose) in infants since excessive usage of decongestant nose drops is contraindicated in early childhood. There is promising early evidence for using nasal irrigation in treating the common cold, respiratory symptoms from occupational exposure, and in post-operative care following sinus or nasal surgeries.
  • Nasal irrigation is generally well tolerated. Use cautiously with history of frequent nosebleeds. If the irrigation liquid is hot, the nose may become irritated.
  • Papain: Papain has shown some benefits in reducing symptoms of sore throat. More high-quality studies are needed in this area.
  • Use cautiously in patients sensitive to papain. Use cautiously in patients being treated for prostatitis. Use Wobenzym®, which contains papain, cautiously, especially in those with bleeding disorders or taking anticoagulants or antiplatelets. Use cautiously with radiation therapy. Avoid in patients with gastroesophageal reflux disease or in patients using immunosuppressive therapy.
  • Peppermint: Peppermint (Mentha piperita) is a flowering plant that grows throughout Europe and North America. Menthol, a constituent of peppermint oil, is sometimes included in inhaled preparations for nasal congestion, including "rubs" that are applied to the skin and inhaled. High quality research is lacking in this area. Essential oils are not intended for internal use.
  • Peppermint oil may be safe in small doses, although multiple adverse effects are possible. When used on the skin, peppermint oil has been associated with allergic/hypersensitivity reactions, skin rash/hives/contact dermatitis, mouth ulcers/sores, chemical burn, and eye irritation. Lung injury has occurred following an injection of peppermint oil. Peppermint oil taken by mouth may cause headache, dizziness, heartburn, anal burning, slow heart rate, or muscle tremor. Very large doses of peppermint oil taken by mouth have resulted in muscle weakness, brain damage, and seizure. Peppermint oil should be used cautiously by people with G6PD deficiency or gallbladder disease. Use in infants or children is not recommended due to potential toxicity. Menthol has been associated with multiple adverse effects, such as serious breathing difficulties, asthma, skin bruising (purpura), and mouth sores. Although small amounts may be safe in non-allergic adults, higher doses may be deadly in humans or cause brain damage. Use on the skin may also cause rash, severe skin damage (necrosis), or kidney damage (interstitial nephritis). Inhalation of large doses of menthol may lead to dizziness, confusion, muscle weakness, nausea, or double vision.
  • Physical therapy: Respiratory therapy has been used in the treatment of chronic bronchitis, and the FLUTTER device has been studied for its beneficial effects. Results are unclear and additional research is needed.
  • Not all physical therapy programs are suited for everyone, and patients should discuss their medical history with a qualified healthcare professional before beginning any treatments. Physical therapy may aggravate pre-existing conditions. Persistent pain and fractures of unknown origin have been reported. Physical therapy may increase the duration of pain or cause limitation of motion. Pain and anxiety may occur during the rehabilitation of patients with burns. Both morning stiffness and bone erosion have been reported in the literature although causality is unclear. Erectile dysfunction has also been reported. Physical therapy has been used in pregnancy and although reports of major adverse effects are lacking the available literature, caution is advised nonetheless. All therapies during pregnancy and breastfeeding should be discussed with a licensed obstetrician/gynecologist before initiation.
  • Propolis: There is some evidence that propolis may help prevent infections with the virus that causes the common cold. Propolis nasal sprays have been suggested as a treatment for runny nose, congestion, and fever in children with nose or throat infections. However, there is currently not enough clinical evidence to support the use of propolis for these indications.
  • Avoid if allergic or hypersensitive to propolis, black poplar (Populas nigra), poplar bud, bee stings, bee products, honey, and Balsam of Peru. Severe allergic reactions have been reported. Use cautiously with asthma or gastrointestinal disorders. Avoid if pregnant or breastfeeding because of the high alcohol content in some products.
  • Selenium: Selenium is a trace mineral found in soil, water, and some foods. It is an essential element in several metabolic pathways. Because selenium is proposed to have a role in immune function, selenium supplementation has been studied in patients with various infections. Some evidence suggests that selenium may promote recovery from bronchitis and pneumonia caused by the respiratory syncytial virus (RSV). Although selenium may correct selenium deficiency in patients with bronchitis, more studies are needed to show its effectiveness in treating respiratory infections.
  • Avoid if allergic or sensitive to products containing selenium. Avoid with history of nonmelanoma skin cancer. Selenium is generally regarded as safe for pregnant or breastfeeding women. However, animal research reports that large doses of selenium may lead to birth defects.
  • Slippery elm: Slippery elm (Ulmus fulva) is commonly used to treat sore throat, most typically taken as a lozenge. While anecdotally reported to be effective, supporting evidence is largely based on traditional evidence and the fact that components of slippery elm appear to possess soothing properties for the throat. Scientific evidence is necessary in this area before a clear conclusion can be drawn.
  • Slippery elm throat lozenges are safe in recommended dosages. Avoid if allergic or hypersensitive to slippery elm. Avoid if pregnant or breastfeeding.
  • Sorrel: Sorrel, in combination with other herbs, may have beneficial effects for acute bronchitis, but it is not clear what dose is safe or effective. Sorrel alone has not been studied for this indication.
  • Avoid large doses of sorrel because there have been reports of toxicity and death. This may be because of the oxalate found in sorrel. Many tinctures contain high levels of alcohol and should be avoided when driving or operating heavy machinery. These sorrel formulations may cause nausea or vomiting when taken with the prescription drugs metronidazole (Flagyl®) or disulfiram (Antabuse®). Avoid if pregnant or breastfeeding.
  • Thyme: Thyme has traditionally been used for the treatment of respiratory conditions including bronchitis and cough. The German Commission E (expert panel), has approved thyme for use in bronchitis. However, due to a lack of available data evaluating thyme alone (not in any combination products), additional study is needed to make a conclusion.
  • Avoid with known allergy/hypersensitivity to members of the Lamiaceae (mint) family or to any component of thyme, or to rosemary (Rosmarinus officinalis). Avoid oral ingestion or non-diluted topical application of thyme oil due to potential toxicity. Avoid topical preparations in areas of skin breakdown or injury, or in atopic patients. Use cautiously in patients with gastrointestinal irritation or peptic ulcer disease. Use cautiously in patients with thyroid disorders. Avoid if pregnant or breastfeeding.
  • Thymus extract: Preliminary evidence suggests that both intramuscular and oral thymus extract may be useful for reducing symptoms of respiratory tract infections. Additional study is needed in this area.
  • Avoid if allergic or hypersensitive to thymus extracts. Use bovine thymus extract supplements cautiously due to potential for exposure to the virus that causes "mad cow disease." Avoid use with an organ transplant or other forms of allografts or xenografts. Avoid if receiving immunosuppressive therapy, with thymic tumors, myasthenia gravis (neuromuscular disorder), untreated hypothyroidism, or if taking hormonal therapy. Avoid if pregnant or breastfeeding; thymic extract increases human sperm motility and progression.
  • Vitamin E: Daily supplementation with oral vitamin E may be beneficial for respiratory infection prevention. Additional research is warranted.
  • Caution is advised when taking vitamin E supplements, as adverse effects and drug interactions are possible. Avoid if allergic or hypersensitive to vitamin E. Avoid with retinitis pigmentosa (loss of peripheral vision). Avoid if pregnant or breastfeeding, unless otherwise directed by a doctor. Use cautiously with bleeding disorders or if taking blood thinners.
  • Wild indigo: Preliminary evidence has shown immunostimulative properties in wild indigo extracts. However, available clinical studies have been conducted using the combination called Esberitox N (Echinaceae purpureae et pallidae radix, Baptisiae tinctoriae radix and Thujae occidentalis herba). Additional study is needed using wild indigo alone to better determine effectiveness for respiratory tract infections.
  • Avoid if allergic or hypersensitive to wild indigo, its constituents, or members of the Fabaceae family. Use cautiously if taking immunosuppressive agents. Avoid if pregnant or breastfeeding.
  • Zinc: Zinc lozenges are advertised as decreasing the symptoms, length, and severity of a cold. However, there are contradictory results regarding the efficacy of zinc formulations in treating duration and severity of common cold symptoms. Although zinc may be beneficial in the treatment of cold symptoms, more studies are needed to clarify which zinc formulations may be most effective, which rhinoviruses are affected by zinc, and if nasal sprays provide a useful alternative application route for zinc treatment. A recent study found no significant differences between zinc nasal spray and placebo.
  • Zinc is generally considered safe when taken at the recommended dosages. Avoid zinc chloride since studies have not been done on its safety or effectiveness. Avoid with kidney disease. Use cautiously if pregnant or breastfeeding.
  • Fair negative scientific evidence:
  • Echinacea: Initial research suggests that echinacea may not be helpful for upper respiratory tract infection treatment in children, possibly because parents are not able to recognize the onset of common cold symptoms soon enough to begin treatment, or because the dose of echinacea for use in children is not clear. There are fundamental differences in causes of upper respiratory tract infections in children versus adults (bacterial versus viral causes; different viruses; different sites of infection; etc). Until additional research is available, echinacea cannot be considered effective in children for the treatment of upper respiratory infections. Furthermore, development of rash has been associated with echinacea use, and therefore the risks may outweigh the potential benefits for children.
  • Avoid if allergic to echinacea, its constituents, or any members of the Asteraceae/Compositae family (ragweed, chrysanthemums, marigolds, daisies). Use cautiously in patients prone to atopic reactions and in those with hemochromatosis and diabetes. Some natural medicine experts discourage the use of echinacea by people with conditions affecting the immune system, such as HIV/AIDS, some types of cancer, multiple sclerosis, tuberculosis, and rheumatologic diseases (such as rheumatoid arthritis or lupus). Use parenteral preparations of echinacea(no longer approved for use in Germany) cautiously. Use tinctures cautiously with alcoholic patients or in patients taking disulfiram or metronidazole. Avoid in patients presenting for anesthesia. Use cautiously if pregnant or breastfeeding.
  • Vitamin C: More than 30 clinical trials including more than 10,000 participants have examined the effects of taking daily vitamin C on cold prevention. Overall, no significant reduction in the risk of developing colds has been observed. In people who developed colds while taking vitamin C, no difference in severity of symptoms has been seen overall, although a very small significant reduction in the duration of colds has been reported (approximately 10% in adults and 15% in children). Additionally, numerous studies have examined the effects of starting vitamin C for common cold treatment after the onset of cold symptoms. Overall, significant benefits have not been observed. Initial evidence reports possible benefits with high doses of vitamin C taken at the onset of symptoms, but without additional evidence this remains indeterminate. Therefore at this time, the scientific evidence does not support the use of vitamin C for either common cold prevention in general or common cold treatment.
  • Avoid if allergic or sensitive to vitamin C product ingredients. Vitamin C is generally considered safe in amounts found in foods. Vitamin C supplements are also generally considered safe in most individuals if taken in recommended doses. Large doses (greater than 2 grams) may cause diarrhea and gastrointestinal upset. Avoid high doses of vitamin C with glucose 6-phosphate dehydrogenase deficiency, kidney disorders or stones, cirrhosis (inflammation of the liver), gout, or paroxysmal nocturnal hemoglobinuria (bleeding disorder). Vitamin C intake from food is generally considered safe if pregnant or breastfeeding. It is not clear if vitamin C supplements in doses higher than Dietary Reference Intake recommendations are safe for pregnant or breastfeeding women. Vitamin C is naturally found in breast milk.

Prevention
  • Cleanliness: Children and adults need to understand the importance of hand washing. Healthcare professionals recommend carrying a bottle of alcohol-based hand rub containing at least 60% alcohol for times when soap and water are not available. These gels kill most germs, and are safe for older children to use themselves. Use cautiously as the overuse of antibacterial cleansers can cause damage to normal bacteria that reside on the skin.
  • Keeping the kitchen and bathroom countertops clean, especially when someone in the family has a common cold, is important. Children's toys should be washed before and after play when a cold is present in the house.
  • Avoiding spreading the virus: Sneezing and coughing into tissues keeps the viruses from spreading. Tissues are discarded right away, and then the hands are washed. Children should sneeze or cough into the bend of their elbow when they do not have a tissue. Avoiding close, prolonged contact with anyone who has a cold is recommended by healthcare professionals. Wearing a facemask, purchased at a local pharmacy, can help in the prevention of spreading or catching a cold virus.
  • Fluids: Water, non-sweetened juices (100% juice, not sweetened), hot teas, and warm soups (especially chicken soup) are all good choices to drink during a cold. Alcohol, caffeine, and cigarette smoke should be avoided as they may cause dehydration and aggravate the symptoms of a cold, including a runny and stuffy nose.
  • Sleep quality: Plenty of sleep and rest helps the body recover from a cold. Healthcare professionals recommend at least eight hours of uninterrupted sleep (not waking up).
  • Temperature and humidity: Keeping the room warm but not overheated where the individual with a cold lives is important. If the air is dry, a cool-mist humidifier or vaporizer can moisten the air and help ease congestion and coughing. A clean humidifier may help to prevent the growth of bacteria and molds.

Author information
  • This information has been edited and peer-reviewed by contributors to the Natural Standard Research Collaboration (www.naturalstandard.com).

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Copyright © 2011 Natural Standard (www.naturalstandard.com)


The information in this monograph is intended for informational purposes only, and is meant to help users better understand health concerns. Information is based on review of scientific research data, historical practice patterns, and clinical experience. This information should not be interpreted as specific medical advice. Users should consult with a qualified healthcare provider for specific questions regarding therapies, diagnosis and/or health conditions, prior to making therapeutic decisions.


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