The ophthalmic H1-antihistamine alcaftadine 0.25%, which has been available by prescription since 2011 for use in patients with allergic conjunctivitis, is now available without a prescription as Lastacaft Once Daily Relief (Allergan) for temporary relief of itchy eyes due to pollen, ragweed, grass, animal hair, and dander in adults and children ≥2 years old. It is the third ophthalmic antihistamine to be approved for over-the-counter (OTC) use (see Table 1).

Fexofenadine (fex oh fen' a deen) hydrochloride (Allegra - Hoechst Marion Roussel) has been approved by the US Food and Drug Administration for treatment of seasonal allergic rhinitis. An active metabolite of terfenadine, fexofenadine is being heavily advertised as "nonsedating...without 'black box' warnings."

Omalizumab (Xolair) is a recombinant humanized monoclonal anti-IgE antibody currently approved by the FDA for treatment of moderate to severe persistent allergic asthma. It has been used off-label for treatment of allergic rhinitis and food allergies. Recently the results of a phase III clinical trial indicated that omalizumab may be effective in treating chronic urticaria as well.

A 0.05% ophthalmic solution of levocabastine hydrochloride (Livostin - Iolab), a histamine H 1 -receptor antagonist, has been approved by the US Food and Drug Administration for treatment of seasonal allergic conjunctivitis. The new drug is a cyclohexylpiperidine derivative with no structural relationship to any other antihistamine.

Cetirizine (Zyrtec, and others) and cetirizine/pseudoephedrine (Zyrtec-D) are becoming available without a prescription this month for treatment of allergic rhinitis and urticaria in adults and children. Cetirizine is the second of the second-generation H1-antihistamines to become available over the counter. Loratadine (Claritin, and others) was the first.Cetirizine has been shown to be more effective than loratadine in suppressing histamine-induced wheals in healthy volunteers (W Carey et al. Drugs Exp Clin Res 2002; 28:243), but no well-controlled clinical trials have established that any...

Astemizole (Hismanal - Janssen), a new antihistamine, was recently marketed in the USA for treatment of seasonal allergic rhinitis and chronic idiopathic urticaria. Like terfenadine (Seldane - Medical Letter, 27:65, 1985), astemizole is claimed to be no more sedating than placebo, but the new drug offers the advantage of a once-daily dosage schedule.

The number of cough remedies available in the USA continues to multiply, but most products contain the same or similar ingredients in varying combinations. Most acute coughs do not require treatment with drugs, especially in children, and suppression of a productive cough may be harmful.

The US Food and Drug Administration has approved the marketing of 5% doxepin hydrochloride cream (Zonalon - GenDerm) for treatment of pruritus due to eczematous dermatoses. Oral doxepin is used as a tricyclic antidepressant (Sinequan, and others).

The physiologic changes that occur with aging can affect the pharmacokinetics and pharmacodynamics of many prescription and over-the-counter drugs, increasing the likelihood of adverse effects.

Acute cough (<3 weeks in duration) generally does not require pharmacologic treatment, especially in children. Suppression of productive cough may be harmful. Management of patients with cough should include elimination of any precipitating factor (e.g., cigarette smoking) and treatment of any underlying cause such as upper airway cough syndrome, gastroesophageal reflux disease, asthma, or other pulmonary disease.