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Nonprescription medications for respiratory symptoms: Facts and marketing fictions.

BACKGROUND
There are many nonprescription (over-the-counter [OTC]) medications available on pharmacy shelves marketed for relief of respiratory symptoms. The number of such medications has been increasing.


OBJECTIVE
This review provides an evidence-based examination of OTC products used for respiratory symptoms.


METHODS
Antihistamines, decongestants, mucolytics, antitussives, and intranasal steroids were selected as the most common OTC medications taken by adults and children for various respiratory symptoms. Controlled clinical trials of efficacy were identified by searching a medical literature data base. Those trials and key publications related to the pharmacokinetics and pharmacodynamics of the products were reviewed.


RESULTS
Comparisons of the various OTC antihistamines' ability to suppress the effects of histamine were related to their clinical benefit. Intranasal corticosteroids are the preferred agents for maintenance therapy of persistent nasal congestion and are highly effective for symptoms of inhalant allergy other than allergic conjunctivitis. The disconnect between marketing claims and evidence was demonstrated for antihistamines and oral alpha-1 adrenergic agonist decongestants. Data for OTC mucolytics and antitussives were insufficient to justify their use based on the evidence.


CONCLUSION
There was little relationship between marketing claims and evidence regarding OTC medications used for respiratory symptoms. Analysis of data supported cetirizine, levocetirizine, and fexofenadine as the most effective of the OTC antihistamines. There were no data that supported the use of oral phenylephrine as a decongestant. Neither OTC mucolytics or antitussives provided sufficient evidence to justify their use.