Patients may be asking health care providers about the safety and effectiveness of Mucinex (Adams), which is being heavily advertised on television and elsewhere for treatment of respiratory congestion. These ads suggest that Mucinex is a new drug, when actually it is an extended-release formulation of guaifenesin, an old expectorant. Guaifenesin increases the volume of secretions in the respiratory tract, which facilitates removal of viscous mucus by coughing. Medical Letter consultants have not been impressed by its effectiveness. Guaifenesin is in the category of drugs - Generally Recognized as Safe - (GRAS) and is included in many prescription and over-the-counter cough remedies,1 but the manufacturer of Mucinex nevertheless sought and received FDA approval. Now the FDA has removed all single-ingredient extended-release guaifenesin products from the market until the manufacturers also apply for and receive approval. Mucinex is available without a prescription for patients 12 years or older and is taken every 12 hours. A bottle of 20 600-mg tablets costs about $12 at a local chain pharmacy.

1. Over-the-counter (OTC) cough remedies. Med Lett Drugs Ther 2001; 43:23.

The first commercially available virucidal tissue, KLEENEX Anti-Viral Tissue (Kimberly-Clark), was recently introduced and is being heavily promoted to the general public. Patients may ask healthcare providers about the usefulness of these products. Theoretically, virucidal tissues could interrupt transmission of viral infections by blocking hand contamination and/or small particle aerosols from nose-blowing, sneezing and coughing.

Patients may be asking about Airborne, a dietary supplement that is being heavily promoted for prevention and treatment of colds. It contains 7 herbal extracts, 3 vitamins, 2 amino acids, selenium, zinc and many other ingredients. Airborne Jr is available for children. There are some concerns. First, there is no conclusive evidence that this product or any of its ingredients prevents colds or shortens their duration. Second, the adult tablet contains 1 g of vitamin C, and the directions for use advise taking 1 tablet at the first sign of a cold and repeating the dose every 3 hours as necessary. Vitamin C in doses higher than 1 g increases oxalate and urate excretion and may cause kidney stones (EN Taylor et al, J Am Soc Nephrol 2004; 15:3225). Third, the safety of this herbal extraction combination has not been established. And with herbs and dietary supplements in general, we only have the manufacturers' word on the label for what's in them.

Echinacea, a plant also called purple coneflower, is widely used as a dietary supplement for prevention and treatment of colds.

Results of a recent study suggested that zinc gluconate may be effective in treating the common cold (SB Mossad et al, Ann Intern Med, 125:81, July 15, 1996). Zinc gluconate lozenges, sometimes combined with vitamin C or other ingredients, are available in pharmacies and health food stores throughout the USA.

Recently, full-page advertisements have appeared in the New York Times and other newspapers promoting the Viralizer (Viral Response Systems, Greenwich, CT), a heated nebulizer-sprayer device marketed for treatment of colds, sore throats, allergy and sinusitis symptoms. The device is available without a prescription for about $30 to $40.