The FDA has approved vigabatrin (vye gá ba trin; Sabril – Lundbeck) for oral use as add-on therapy for complex partial seizures in adults who are refractory to several antiepileptic drugs and as monotherapy for infantile spasms. Vigabatrin has been available in other countries for many years. Because of its potential for retinal toxicity, it will be available in the US only through a restricted distribution program called SHARE (Support, Help and Resources for Epilepsy). Prescribers and pharmacists distributing the drug must register, and patients must undergo visual field testing.

The FDA has approved ezogabine (ee-ZOE-ga-been; Potiga – GSK/Valeant) for oral adjunctive treatment of partial-onset seizures in adults. Ezogabine is available in Europe as retigabine (Trobalt).

Itraconazole (Sporanox - Janssen), an oral antifungal triazole that has been available in the USA since 1992 for treatment of deep fungal infections (Medical Letter, 35:7, 1993), is now being marketed for treatment of dermatophyte infections of the toenails, with or without fingernail involvement.

The FDA has approved 2 oral drugs for treatment of idiopathic pulmonary fibrosis (IPF). Pirfenidone (Esbriet) has been available in Europe since 2011 and in Canada since 2012. Nintedanib (Ofev) is available only in the US.

The ability of grapefruit juice to increase serum concentrations of drugs was first discovered during a study of the effect of ethanol on felodipine (Plendil) pharmacokinetics. Double-strength grapefruit juice used to disguise the taste of ethanol resulted in higher than expected serum concentrations of felodipine (DG Bailey et al, Clin Invest Med 1989; 12:357).

Pregabalin (Lyrica - Pfizer), a structural analog of gamma-aminobutyric acid (GABA) similar to gabapentin (Neurontin - Pfizer, and others), which recently became available generically, has been approved by the FDA for treatment of neuropathic pain associated with postherpetic neuralgia (PHN) and diabetic peripheral neuropathy (DPN), and for adjunctive treatment of partial onset seizures in adults with epilepsy.

The FDA has approved tenofovir alafenamide (Vemlidy – Gilead) for treatment of chronic hepatitis B virus (HBV) infection in adults with compensated liver disease. It is the first single-drug product containing tenofovir alafenamide (TAF), a prodrug of the nucleotide reverse transcriptase inhibitor tenofovir, to become available; several combination products containing TAF are approved for treatment of HIV-1 infection. Tenofovir disoproxil fumarate (TDF; Viread – Gilead), another tenofovir prodrug, has been used for many years for treatment of chronic HBV infection; a generic...

Four different desk-top systems are now widely used in physicians'; offices to measure blood chemistries. The Ektachem DT (Kodak) and Reflotron (Boehringer Mannheim), reviewed previously in The Medical Letter (volume 30, page 119, 1988; volume 31, page 90, 1989), resemble the Seralyzer (Miles Diagnostics) in cost; the Vision (Abbott), which is fully automated, is much more expensive.

When patents expire on brand-name drugs and generic formulations become available, patients and managed care organizations may express a preference for the lower-cost generics. Are they equivalent to the brand-name product?

The FDA has approved an extended-release (XR) formulation of the benzodiazepine alprazolam (Xanax XR - Pfizer) for treatment of panic disorder, with or without agoraphobia. The new formulation is intended to reduce the need for frequent dosing and problems of interdose anxiety. This review describes the effectiveness of the extended-release formulation, as well as sections on dependence, abuse and withdrawal, adverse effects, and drug interactions. The review concludes with an overall assessment of the drug's efficacy and cost.