Adefovir dipivoxil (Hepsera - Gilead), a nucleotide analog, has been approved by the FDA for oral treatment of chronic active infection with hepatitis B virus (HBV). In 1999, because of concerns about renal toxicity, the FDA rejected a higher-dosage formulation of adefovir for treatment of HIV infection.

The FDA has approved recombinant interferon alfa-2a conjugated to polyethylene glycol (Pegasys - Roche) alone or with oral ribavirin (Copegus - Roche) for treatment of adults with chronic hepatitis C virus (HCV) infections not previously treated with interferon alpha. The standard of care for treatment of most patients with hepatitis C has been once-weekly injections of peginterferon alfa-2b (PEG-Intron -Schering) plus oral ribavirin (Rebetol - Schering) (Medical Letter 2001; 43:54).

The FDA has approved subcutaneous injection of methylnaltrexone (Relistor - Wyeth/Progenics), a selective mu-opioid receptor antagonist, for treatment of opioid-induced constipation in patients with advanced illness (such as incurable cancer or end-stage chronic obstructive pulmonary disease) who are receiving palliative care.

The most effective drugs available for treatment of tobacco dependence are bupropion (Zyban, and others and varenicline (Chantix). The FDA recently ordered the manufacturers of both to add boxed warnings about the risk of psychiatric symptoms and suicide to their prescribing information (FDA Alert, 7/1/2009).

Brivaracetam (Briviact – UCB), an analog of levetiracetam (Keppra, and others), has been approved by the FDA for adjunctive treatment of partial-onset seizures in patients ≥16 years old. New drugs for epilepsy are often approved initially only as adjunctive treatment for partial seizures.

Since The Medical Letter last reviewed the choice of benzodiazepines (Volume 23, page 41, 1981), several new drugs have been marketed and some old ones are now available generically. Most of the benzodiazepines available for oral use in the USA are listed in the table on page 28.

Fluconazole (Diflucan - Roerig), an antifungal azole, was recently approved by the US Food and Drug Administration for oral and intravenous (IV) treatment of cryptococcal meningitis and various forms of candidiasis. Both cryptococcal meningitis and candidiasis occur frequently in patients with AIDS, organ transplants, or cancer.

Azelastine hydrochloride, a histamine-H1 receptor antagonist, has been marketed as a 0.1% nasal spray (Astelin - Wallace) for treatment of seasonal allergic rhinitis. Corticosteroid and cromolyn sodium nasal sprays are also available for this indication (Medical Letter, 37:5, 1995). Cromolyn sodium (Nasalcrom) has now been approved for over-the-counter use.

Carnitine is a naturally occurring amino acid derivative essential for transport of long-chain fatty acids into mitochondria. It is advertised on the Internet as a dietary supplement that can promote weight loss, increase energy, enhance athletic performance and slow aging. Levocarnitine (Carnitor - Sigma-Tau) has been FDA approved for oral and parenteral treatment of primary carnitine deficiency since 1986. Products containing levocarnitine and its synthetic derivative acetyl-L-carnitine are available as dietary supplements in the US.

The FDA has approved the marketing of extended release (ER) ranolazine (Ranexa - CV Therapeutics) for treatment of chronic angina in patients who have not achieved an adequate response with other antianginal drugs. It should be used in combination with a nitrate, a beta-blocker or the dihydropyridine calcium-channel blocker amlodipine (Norvasc), and appears to be more effective in men. The labeling for ranolazine specifies amlodipine as the calcium-channel blocker of choice because the use of other dihydropyridines with ranolazine has not been studied, and use with diltiazem (Cardizem, and...