Intravenous immunoglobulin (IVIG) has 6 FDA approved indications and is prescribed off-label for many others. How many of these uses are justified is controversial.

(Kodak) perform clinical chemistry tests using desk-top instruments, microliter samples and postage-stamp-sized analytical slides containing dry reagents layered on clear polyester and mounted in plastic. The system requires no wet reagents, except for electrolyte determinations, and is designed to require a minimum amount of training to operate. A single analysis takes about five minutes.

The Reflotron (Boehringer Mannheim), a desk-top colorimetric reflectance analyzer that weighs 12 pounds, can do clinical chemistry tests on 30 l of whole blood, plasma or serum, using multilayered strips containing dry chemicals. A single test takes two to three minutes.

Recombinant alpha interferon has been marketed in the USA for treatment of hairy-cell leukemia, genital warts, and AIDS-related Kaposi's sarcoma (Medical Letter, 28:78, 1986; 30:70, 1988). Recent reports indicate it may also be useful for treatment of chronic viral hepatitis. Recombinant alpha interferon is available as alfa-2a (Roferon-A - Roche) or alfa-2b (Intron A - Schering), which are identical except for one amino acid.

Altretamine (Hexalen - US Bioscience; Hexastat - Rh ne-Poulenc in Canada), formerly known only by its chemical name, hexamethylmelamine, was recently approved by the US Food and Drug Administration as a single agent for palliative oral treatment of persistent or recurrent ovarian cancer.

Quinapril (Accupril - Parke-Davis), an angiotensin-converting enzyme (ACE) inhibitor, has been approved by the US Food and Drug Administration (FDA) for treatment of hypertension. ACE inhibitors are now widely used for this indication (Medical Letter, 33:33, 1991).

Pravastatin - Bristol-Myers Squibb) and simvastatin (Zocor -Merck), two new inhibitors of cholesterol synthesis similar to lovastatin (Mevacor - Merck), have now been marketed in the USA for treatment of hypercholesterolemia. Lovastatin (Medical Letter, 29:99, 1987) is the most frequently prescribed of all cholesterol-lowering drugs in the USA. Pravastatin and simvastatin were previously reviewed in The Medical Letter when they became available in Canada (volume 33, page 18, 1991).

Some patients may ask physicians about the effectiveness and safety of homeopathic drugs, which are marketed through health food stores, pharmacies, direct mail and person-to-person sales, and promoted for use in a wide range of disorders.

The US Food and Drug Administration has ordered removal of phenylpropanolamine from over-the-counter cold remedies and weight loss aids. The FDA based its decision on a recent study showing an increased risk of hemorrhagic stroke in young women taking the drug.

The FDA has approved a new formulation of fluoxetine for once-weekly maintenance treatment of depression in patients who have responded to daily fluoxetine (Prozac).