Influenza; Strep throat; Bird flu; Avian influenza
The following are some food and fluid recommendations. Most will not cure a cold, but they may help a person deal better with the symptoms:
Despite a few studies that suggest that large doses of vitamin C may reduce the duration of a cold, most of the scientific evidence finds no benefit. Taking high doses of vitamin C is not recommended, for the following reasons:
In addition, a review of evidence suggests that taking large doses of vitamin C after the onset of cold symptoms does not improve the symptoms or shortens the duration of the cold.
Zinc appears to influence the immune system and it may have a direct effect on viruses. How it works is not entirely clear, however. Zinc preparations in lozenge or nasal gel form are now available as cold treatments. Studies are very mixed on the effects of zinc on colds. A review of available studies comparing zinc treatment to placebo ("sugar pill") found only one high-quality study, which showed that zinc nasal gels might provide a benefit. The overall benefit of zinc in the prevention of colds remains unproven. In any case, no one with an adequate diet and a healthy immune system should take zinc for prolonged periods, for the purpose of preventing colds.
Side Effects. Side effects, particularly of the lozenges form, include the following:
Food and Drug Interactions. Zinc may also interact with drugs or other elements:
Many people take medications to reduce mild pain and fever. Adults most often choose aspirin, ibuprofen (Advil), or acetaminophen (Tylenol).
The following are recommendations for children:
Nasal strips (such as Breathe Right) are placed across the lower part of the nose and pull the nostrils open. These strips may open the nasal passages and ease congestion due to a cold, sinusitis, or hay fever. As of yet, there is no scientific evidence that they offer such benefits.
A nasal wash can be helpful for removing mucus from the nose. A saline solution can be purchased at a drug store or made at home. One study reported that neither a homemade solution (using one teaspoon of salt and one pinch of baking soda in a pint of warm water) nor a commercial hypertonic saline nasal wash had any effect on symptoms. Further, one preliminary study found that over-the-counter saline nasal sprays that contain benzalkonium chloride as a preservative may actually worsen symptoms and infection.
Some physicians, however, advocate a traditional nasal wash that has been used for centuries and is different from that used in most studies. It contains no baking soda and uses more fluid for each dose and less salt. The nasal wash should be performed several times a day.
A simple method for administering a nasal wash:
The solution may also be inserted into the nose using a large rubber ear syringe, available at a pharmacy. In this case, the process is the following:
Nasal-delivery decongestants are applied directly into the nasal passages with a spray, gel, drops, or vapors. Nasal forms work faster than oral decongestants and have fewer side effects. They often require frequent administration, although long-acting forms are now available. Ingredients and brands of nasal decongestants include the following:
Long Acting Nasal-Delivery Decongestants. They are effective in a few minutes and remain so for 6 - 12 hours. The primary ingredient in long-acting decongestant is:
Short-Acting Nasal-Delivery Decongestants. The effects usually last about 4 hours. The primary ingredients in short-acing decongestants are:
Dependency and Rebound. The major hazard with nasal-delivery decongestants, particularly long-acting forms, is a cycle of dependency and rebound effects. The 12-hour brands pose a particular risk for this effect. This effect works in the following way:
Tips for Use. The following precautions are important for people taking nasal decongestants:
Oral decongestants also come in many brands, which mainly differ in their ingredients. The most common active ingredient are pseudoephedrine (Sudafed, Actifed, Drixoral) or phenylephrine (Sudafed PE and many other cold products) .
Side Effects of Decongestants. Decongestants have certain adverse effects, which are more apt to occur in oral than nasal decongestants and include the following:
Avoid combinations of oral decongestants with alcohol or certain drugs, including monoamine oxidase inhibitors (MAOI) and sedatives
Individuals at Risk for Complications from Decongestants. People who may be at higher risk for complications are those with certain medical conditions, including disorders that make blood vessels highly susceptible to contraction. Such conditions include the following:
Anyone with the above conditions should not use either oral or nasal decongestants without a doctor's guidance. In addition, people taking medications that increase serotonin levels, such as certain antidepressants, anti-migraine agents, diet pills, St. John's wort, and methamphetamine, should avoid decongestants. The combinations can cause blood vessels in the brain to narrow suddenly, causing severe headaches and even stroke.
Others who should use these drugs with caution are the following (consult your health care provider):
In October 2007, drug manufacturers voluntarily withdrew from the market all oral cough and cold products, including decongestants, aimed at children under 2, due to potential harm from misuse. In late 2008, the Consumer Healthcare Products Association, which represents most of the US makers of nonprescription over-the-counter cough and cold medicines in children, began voluntarily modifying its products' labels to read "Do Not Use in Children Under 4." This action is supported by the FDA. Note that no products are being removed from the shelves this time. Therefore, there may be a transition period in which the instructions for use on different bottles of the same medicine may be different -- some may read "Do not Use" under age 2, while others will have the new recommendation of age 4. The FDA recommends parents follow the instructions on the bottle they bought.
Under no circumstances should children be given adult medicines, including over-the-counter medications.
Major studies have indicated that over-the-counter cough medicines are not very effective, but they are also not harmful.
Medications that contain both a cough suppressant and an expectorant are not useful and should be avoided. Medicated cough drops that contain dextromethorphan are not very useful. A patient is just as likely to find relief from hard candy or lozenges.
Prescription cough medications with small doses of narcotics are available. They are usually reserved for lower respiratory infections with significant coughs.
Sore throats that are associated with colds are generally mild. The following may be helpful:
If soreness in the throat is very severe and does not respond to mild treatments, the patient or parent should check with the physician to see if a strep throat is present, which would require antibiotics. [See "What is Strep Throat?" in the Diagnosis section of this report.]
Dozens of remedies are available that combine ingredients aimed at more than one cold or flu symptom. In general, they do no harm, but they have the following problems:
Note on Antihistamines. Many combination remedies contain antihistamines. Antihistamines are used for allergies and are not generally recommended to relieve the symptoms of the common cold. Some evidence suggests, however, that they may have some value.
First-generation antihistamines may reduce cold symptoms. Their benefits for the cold are likely to be due to the drowsiness they cause. Such antihistamines include Benadryl, Tavist, and Chlor-Trimeton. The newer, second-generation antihistamines (Claritin, Allegra, Zyrtec) do not have these effects and also appear to have no benefits against colds.
Herbal remedies and dietary supplements are not regulated by the FDA. This means that manufacturers and distributors do not need FDA approval to sell their products. In addition, any substance that affects the body's chemistry can, like any drug, produce side effects that may be harmful. There have been numerous reported cases of serious and even deadly side effects from herbal products.
The following are special concerns for people taking natural remedies for colds or influenza:
American Academy of Pediatrics Committee on Infectious Diseases. Recommended childhood and adolescent immunization schedule: United States, 2005. Pediatrics. 2005 Jan;115(1):182.
Caruso TJ, Prober CG, Gwaltney JM Jr. Treatment of naturally acquired common colds with zinc: a structured review. Clin Infect Dis. 2007;45(5):569-74.
Centers for Disease Control and Prevention. Key Facts About Seasonal Influenza (Flu). Available online.
Centers for Disease Control and Prevention. 2007-08 Influenza Prevention & Control Recommendations: Vaccination of Specific Populations. Available online.
Centers for Disease Control and Prevention. Acute Respiratory Disease Associated with Adenovirus Serotype 14 -- Four States, 2006-2007. MMWR. 2007;56(45):1181-84.
Centers for Disease Control and Prevention. FDA Approves New Laboratory Test To Detect Human Infections With Avian Influenza A/H5 Viruses. February 3, 2006.
Harper SA, Fukuda K, Uyeki TM, Cox NJ, Bridges CB. Prevention and Control of Influenza: Recommendations of the Advisory Committee on Immunization Practices (ACIP). MMWR Recomm Rep. 2005 Jul 29;54(RR-8):1-40.
Hayden GF, Turner RB. Acute Pharyngitis. In: Behrman RE, Kliegman RM, Jenson HB, eds. Behrman: Nelson Textbook of Pediatrics, 17th ed. Philadelphia, Pa: Saunders; 2004.
Interagency Task Force on Antimicrobial Resistance. Executive Summary: 2006 Annual Report on Progress on "A Public Health Action Plan to Combat Antimicrobial Resistance." Draft release, June 2007. Available online.
Jefferson T, Demichelli V, Rivetti D, Jones M, Di Pietrantonj C, Rivetti A. Antivirals for influenza in healthy adults: systematic review. Lancet 2006 Jan 28;367(9507):303-13.
Recommendations of the Advisory Committee on Immunization Practices (ACIP), 2008. MMWR. July 17, 2008/57(Early Release);1-60.
Reveiz L, Cardona AF, Ospina EG. Antibiotics for acute laryngitis in adults. Cochrane Database Syst Rev. 2007 Apr 18;(2):CD004783.
Sasazuki S, Sasaki S, Tsubono Y, Okubo S, Hayashi M, Tsugane S. Effect of vitamin C on common cold: randomized controlled trial. Eur J Clin Nutr. 2006;60(1):9 - 17.
Shah SA, Sander S, White CM, Rinaldi M, Coleman CI. Evaluation of echinacea for the prevention and treatment of the common cold: a meta-analysis. Lancet Infect Dis. 2007;7(7):473-80.
Simasek M, Blandino DA. Treatment of the common cold. Am Fam Physician. 2007;75(4):515-20.
Taverner D, Latte J. Nasal decongestants for the common cold. Cochrane Database Syst Rev. 2007 Jan 24;(1):CD001953.
U.S. Food and Drug Administration: Nonprescription Drugs and Pediatric Advisory Committee Meeting. Joint Meeting of the Nonprescription Drugs Advisory Committee and the Pediatric Advisory Committee October 18-19, 2007. Available online.
World Health Organization: Neuraminidase Inhibitor Susceptibility Network. Monitoring of neuraminidase inhibitor resistance among clinical influenza virus isolates in Japan during the 2003-2006 influenza seasons. Weekly epidemiological record. 2007;82(17):149-50.
World Health Organization. Cumulative Number of Confirmed Human Cases of Avian Influenza A/(H5N1) Reported to WHO. December 16, 2008. Available online.
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