Isosorbide mononitrate, the major active metabolite of isosorbide dinitrate, was first approved in the USA for oral use in patients with chronic stable angina in 1992 (Medical Letter, 34:61, 1992). Now an extended-release formulation of isosorbide mononitrate (Imdur -Key) has been approved by the US Food and Drug Administration.

Venlafaxine hydrochloride (Effexor - Wyeth-Ayerst) was recently approved by the US Food and Drug Administration for treatment of depression. An aminomethyl-benzyl- cyclohexanol, it is chemically related to bupropion (Wellbutrin).

Lansoprazole (Prevacid -TAP), a proton pump inhibitor similar to omeprazole (Prilosec - Medical Letter, 32:19, 1990), has been approved by the US Food and Drug Administration for short-term treatment of active duodenal ulcer and erosive reflux esophagitis and for long-term treatment of chronic hypersecretory conditions, including the Zollinger-Ellison syndrome.

Several readers have asked the Medical Letter to evaluate the effectiveness and safety of exogenous melatonin for treatment of insomnia and jet lag. Melatonin has not been approved by the US Food and Drug Administration (FDA), but is available in health food stores and apparently is being used as self-medication to treat a wide variety of disorders.

Topiramate (Topamax - Ortho-McNeil) has been approved by the US Food and Drug Administration (FDA) for oral use as an adjunct to other drugs in adult patients with partial seizures. Since this diagnostic category includes the largest number of patients with refractory epilepsy, new drugs with antiepileptic activity are usually tried first for this indication. Topiramate (toe pyre' a mate) is a structurally unique agent chemically related to the D-enantiomer of fructose.

Micronized fenofibrate (Tricor - Abbott), a fibric acid derivative structurally similar to clofibrate (Atromid-S, and others) and gemfibrozil (Lopid, and others), has been approved by the FDA for treatment of hypertriglyceridemia. Increased serum triglyceride concentrations have been associated with an increased risk of coronary heart disease (J Jeppesen et al, Circulation, 97:1029, 1998).

Infliximab, a monoclonal antibody that inhibits tumor necrosis factor, has received an accelerated approval from the FDA for intravenous treatment of moderate to severe Crohn's disease refractory to other medical treatment.

A long-pulse ruby laser (EpiLaser), has been cleared by the FDA for use in "permanent hair reduction."

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

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.