When patents expire on brand-name drugs and generic formulations become available, patients and managed care organizations may express a preference for the lower-cost generics. Are they equivalent to the brand-name product?

Nizatidine (Axid - Lilly), a new H2-receptor antagonist similar to cimetidine (Tagamet), ranitidine (Zantac) and famotidine (Pepcid), was recently approved by the US Food and Drug Administration for treatment of active duodenal ulcer and for maintenance therapy after healing. Cimetidine, ranitidine and famotidine are also approved for treatment of pathological hypersecretory conditions such as Zollinger- Ellison syndrome; cimetidine is approved in addition for treatment of gastric ulcers.

The FDA has approved marketing of the corticosteroid budesonide in an oral inhalatoin powder formulation (Pulmicort Turbuhaler - Astra) for maintenance treatment of asthma in adults and children at least six years old. Budesonide has been available in the USA as an intranasal spray (Rhinocort) for treatment of allergic rhinitis since 1994 and has been used for inhalation treatment of asthma in Canada and Europe for ten years.

Older patients are especially susceptible to drug-induced cognitive impairment. They are more likely to be taking multiple drugs, to have higher blood levels of those drugs because of renal or hepatic dysfunction, and to have pre-existing cognitive problems that make it difficult to detect the role of drugs causing new symptoms or making old ones worse.

Ofloxacin (Floxin - McNeil, Ortho), a new fluoroquinolone antibacterial agent, was recently marketed in the USA for oral treatment of various infections caused by susceptible microorganisms. Ofloxacin is the third fluoroquinolone to become available in this country. Norfloxacin (Noroxin - Medical Letter, 29:25, 1987) is marketed only for treatment of urinary tract infections. Ciprofloxacin (Cipro - Medical Letter, 30:11, 1988), like ofloxacin, is approved for use in a variety of infections.

Enoxacin (en ox' a sin; Penetrex - Rh ne-Poulenc Rorer), a fluoroquinolone antimicrobial for oral use, has now been marketed in the USA for treatment of urinary tract infections and uncomplicated urethral or cervical gonorrhea.

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.

Primary hypothyroidism is usually the result of Hashimoto's thyroiditis, thyroidectomy for hyperthyroidism, goiter or cancer, or radioactive iodine therapy for hyperthyroidism.

Temafloxacin (Omniflox - Abbott) and lomefloxacin (Maxaquin - Searle) are the latest fluoroquinolone antimicrobial agents to be approved by the US Food and Drug Administration (FDA) for oral treatment of various infections. Previously marketed include norfloxacin (Noroxin - Medical Letter, 29:25, 1987), ciprofloxacin (Cipro - Medical Letter, 30:11, 1988), and ofloxacin (Floxin - Medical Letter, 33:71, 1991). Norfloxacin is marketed only for treatment of urinary tract infections, and lomefloxacin only for treatment of urinary tract infections and bronchitis known to be caused by...

Adenosine (Adenocard - Fujisawa), an endogenous purine nucleoside, was recently approved by the US Food and Drug Administration for intravenous treatment of paroxysmal supraventricular tachycardia, including Wolff-Parkinson-White (WPW) syndrome. Adenosine is not approved for and has not been effective in treating atrial flutter, atrial fibrillation, or ventricular tachycardias.