Azelastine hydrochloride, a histamine-H1 receptor antagonist, has been marketed as a 0.1% nasal spray (Astelin - Wallace) for treatment of seasonal allergic rhinitis. Corticosteroid and cromolyn sodium nasal sprays are also available for this indication (Medical Letter, 37:5, 1995). Cromolyn sodium (Nasalcrom) has now been approved for over-the-counter use.

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.

An intranasal formulation of the corticosteroid triamcinolone (Nasacort - Rh ne- Poulenc Rorer) was recently approved by the US Food and Drug Administration for once-daily treatment of seasonal and perennial allergic rhinitis.

Olopatadine hydrochloride (Patanol - Alcon), a propilidinedibenzoxypin derivative, has recently been marketed in a 0.1% ophthalmic solution for prevention of itching due to allergic conjunctivitis in adults and children more than three years old. It is the first drug for this indication that both inhibits mast cell degranulation and is a selective histamine H1 receptor antagonist (NA Sharif et al, J Pharmacol Exp Ther, 278:1252, 1996).

Ketorolac (kee' toe role ak) tromethamine 0.5%, a nonsteroidal anti-inflammatory drug (NSAID) previously available for parenteral and oral administration (Toradol - Medical Letter, 32:79, 1990), has now been approved for ophthalmic use (Acular - Allergan, Fisons) to relieve itching in seasonal allergic conjunctivitis. NSAIDs decrease prostaglandin concentrations in the eye, which theoretically might contribute to a decrease in itching. Several other NSAIDs are available for ophthalmic use in the USA, but none is marketed for this indication. Flurbiprofen (Ocufen) and suprofen (Profenal) ...

Nedocromil sodium (Tilade - Fisons), an anti-inflammatory drug similar to cromolyn sodium (Intal - Fisons), although chemically unrelated, is now available in the USA as a metered-dose inhaler for maintenance treatment of mild to moderate asthma.

Zafirlukast (za fir loo kast; Accolate - Zeneca), the first leukotriene receptor anta-gonist approved by the US Food and Drug Administration, is now being heavily promoted for oral maintenance treatment of chronic asthma in patients more than 12 years old. It is not recommended for treatment of acute asthma.

Lodoxamide, a mast cell stabilizer, has been marketed in a 0.1% ophthalmic solution (Alomide - Alcon) for treatment of vernal keratoconjunctivitis.

Patients with seasonal allergies often experience nasal itching and congestion, sneezing, rhinorrhea, and itchy, watery eyes. Oral, intranasal, and ophthalmic preparations are widely available over the counter (OTC) for relief of symptoms. Prescription products for management of allergic rhinitis and allergic conjunctivitis are reviewed separately.

Salmeterol xinafoate (Serevent - Allen & Hanburys), a long-acting β 2 -selective adrenergic agonist for inhalation, has been approved by the US Food and Drug Administration for maintenance treatment of asthma, with or without concurrent use of inhaled corticosteroids. Salmeterol is not recommended for acute treatment of bronchospasm.