A topical formulation of 0.75% metronidazole gel (MetroGel - Curatek), an antibacterial, antiparasitic agent, was recently approved by the US Food and Drug Administration for treatment of rosacea.

Levamisole (Janssen), an old antiparasitic drug widely used for treatment of ascariasis in animals, is now available from the National Cancer Institute (NCI) for investigational use with fluorouracil (5-FU; Adrucil; and others) as an adjuvant for treatment of resectable colon cancer that has metastasized to regional lymph nodes (Dukes stage C).

An oral formulation of mesalamine (5-aminosalicylic acid, 5-ASA, Asacol - Proctor & Gamble), was recently approved by the US Food and Drug Administration (FDA) for treatment of mildly to moderately active ulcerative colitis; it has not been approved for maintenance of remissions. Olsalazine (Dipentum), a similar drug (Medical Letter, 32:105, 1990), is approved for maintenance of remissions but not for treatment.

Interest in surgical treatment of Parkinson's disease has increased as the limitations of medical treatment have become apparent (Medical Letter, 35:31, 1993). Two approaches have been used. The first is transplantation of dopamine-producing cells into the patient's brain. The second is stereotactic surgery in areas of the brain that modify movement.

An intranasal formulation of the corticosteroid budesonide (Rhinocort Nasal Inhaler - Astra) was recently approved by the US Food and Drug Administration for treatment of seasonal or perennial allergic rhinitis in adults and children and nonallergic perennial rhinitis in adults. Budesonide has been available in Canada and Europe for several years for inhalation treatment of both allergic rhinitis and asthma.

A drug that combines the neutral sulfate salts of dextroamphetamine and racemic amphetamine with the dextro isomer of amphetamine saccharate and d,l amphetamine aspartate (Adderall - Richwood Pharmaceutical) has recently been promoted for treatment of children with Attention-Deficit/Hyperactivity Disorder (ADHD). This same mixture of amphetamine salts was previously marketed as Obetrol for treatment of obesity.

Dirithromycin (Dynabac - manufactured by Lilly, distributed by Bock), an oral macrolide antibiotic chemically similar to erythromycin, clarithromycin (Biaxin) and azithromycin (Zithromax), has been approved for marketing by the US Food and Drug Administration (FDA).

Dalteparin (Fragmin - Pharmacia), the second low-molecular-weight heparin to be marketed in the USA, is now available for prevention of deep vein thrombosis in high-risk patients after abdominal surgery. Enoxaparin (Lovenox -Rh ne-Poulenc Rorer) was approved in 1993 for prevention of deep vein thrombosis after hip replacement (Medical Letter, 35:75, 1993) and later approved for use in knee replacement. Five other low-molecular-weight heparins and one heparinoid are under investigation in the USA (MJ Cziraky and SA Spinler, Clin Pharm, 12:892, 1993).

Quetiapine (Seroquel - Zeneca), a dibenzothiazepine derivative, has been approved by the FDA for treatment of schizophrenia and other psychotic disorders. It is a new addition to the 'atypical' antipsychotics, which include olanzapine (Zyprexa - Medical Letter, 39:5, 1997), risperidone (Risperdal) and clozapine (Clozaril). Atypical antipsychotic drugs generally are less likely to cause extrapyramidal symptoms than older drugs such as haloperidol (Haldol, and others) or the phenothiazines.

The FDA has approved marketing of Plan B (Women's Capital Corporation), an emergency contraceptive "pill pack"that contains two 0.75-mg tablets of levonorgestrel.