Phytoestrogens, plant compounds that are converted to estrogens in the gut, are widely promoted as "natural"substitutes for estrogen in hormone replacement therapy.

The FDA has approved exemestane, an aromatase inhibitor, for the treatment of postmenopausal women with advanced breast cancer that has progressed during treatment with tamoxifen.

Ciclopirox nail lacquer (Penlac - Dermik) has been approved by the FDA for treatment of mild-to-moderate onychomycosis due to Trichophyton rubrum, without involvement of the lunula. The drug has been available for many years as a lotion and cream (Loprox) for treatment of cutaneous fungal infection

Rivastigmine tartrate (Exelon - Novartis), a carbamate-based cholinesterase inhibitor, is now being marketed for treatment of patients with dementia due to Alzheimer's disease.

Galantamine hydrobromide (Reminyl), a tertiary alkaloid and phenanthrene derivative extracted from daffodil bulbs, is now being marketed for oral treatment of mild to moderate Alzheimer's disease. Galantamine is the fourth acetylcholinesterase inhibitor approved for this indication.

Since the last Medical Letter article on glucosamine for osteoarthritis (vol.39, page 91, September 26, 1997), more data have become available. Glucosamine is available in US pharmacies and health food stores as sulfate, hydrochloride or n-acetyl salt.

Dexmethylphenidate (Focalin - Novartis), a new formulation of methylphenidate (Ritalin, and others) is now available for treatment of attention deficit/hyperactivity disorder (ADHD). Dexmethylphenidate is the d-threo-enantiomer of racemic methylphenidate. "Now the right half may be all your patients need," said a recent ad. Focalin is the third new methylphenidate formulation marketed in the last two years.

The FDA has added a "black box" warning about the risks of QT prolongation and the potentially fatal torsades de pointes (TdP) ventricular tachycardia to the labeling of droperidol (Inapsine - Akorn), an antiemetic used mostly in anesthesia. The Canadian Health Protection Branch has issued a similar warning. Some anesthesiologists have written to The Medical Letter to express their displeasure with these warnings.

Anastrozole (Arimidex - AstraZeneca, Medical Letter 1996; 38:61), an aromatase inhibitor, has received accelerated approval from the FDA for adjuvant treatment of postmenopausal women with early hormone-receptor-positive breast cancer. The drug was approved for treatment of postmenopausal women with metastatic breast cancer in 1996.

Cinacalcet hydrochloride (Sensipar - Amgen) has been approved by the FDA for treatment of secondary hyperparathyroidism in adult patients with chronic kidney disease on dialysis and treatment of hypercalcemia in patients with parathyroid carcinoma.