Modafinil (Provigil - Cephalon; Alertec - Draxis in Canada), first approved by the FDA in 1999 for treatment of excessive daytime sleepiness associated with narcolepsy (Medical Letter 1999; 41:30), has now also been approved for treatment of patients with excessive sleepiness due to obstructive sleep apnea/hypopnea syndrome (OSAHS) or shift work sleep disorder (SWSD) (DSM-IV, text revision, Washington, DC: American Psychiatric Association, 2000, page 622).

Imiquimod cream 5% (Aldara - 3M), an immune modifier previously approved for treatment of genital and perianal warts (Medical Letter 1997; 39:118), has now been approved by the FDA for treatment of actinic keratoses (AKs) on the face or scalp, and may also be approved soon for treatment of basal cell carcinoma. It produces apoptosis in malignant, but not normal, human keratinocytes (M Sch÷n et al, J Natl Cancer Inst 2003; 95:1138).

Sertaconazole nitrate (Ertaczo - OrthoNeutrogena), an imidazole antifungal similar to clotrimazole and miconazole, has been approved by the FDA as a 2% cream for topical treatment of interdigital tinea pedis infection. It has been available in Europe for many years.

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 first commercially available virucidal tissue, KLEENEX Anti-Viral Tissue (Kimberly-Clark), was recently introduced and is being heavily promoted to the general public. Patients may ask healthcare providers about the usefulness of these products. Theoretically, virucidal tissues could interrupt transmission of viral infections by blocking hand contamination and/or small particle aerosols from nose-blowing, sneezing and coughing.

Apomorphine (Apokyn - Mylan/Bertek), an injected non-ergot dopamine agonist, was recently approved by the FDA for intermittent subcutaneous (SC) treatment of hypomobility ("off" episodes) in patients with advanced Parkinson's disease. It has been available in Europe for many years.

The FDA has approved emtricitabine/tenofovir (Truvada - Gilead) and abacavir/lamivudine (Epzicom - GSK), two new fixed-dose combinations of nucleoside/nucleotide reverse transcriptase inhibitors (NRTIs), for once-daily use in treatment of HIV infection. Two other fixed-dose NRTI combinations were previously approved for twice-daily dosing. Dual NRTI therapy is generally used in either an NNRTI (non-nucleoside reverse transcriptase inhibitor)-based or a PI (protease inhibitor)-based regimen.

Angiotensin receptor blockers (ARBs) are widely used as an alternative to angiotensin converting enzyme (ACE) inhibitors for treatment of hypertension because they lower blood pressure without inducing a cough. It has not been established that they provide the same cardiac benefits as ACE inhibitors. Recently, an editorial in the British Medical Journal suggested that ARBs may increase the risk of myocardial infarction.

Serious adverse interactions between drugs continue to be reported. Many of these are due to inhibition or induction of cytochrome P450 (CYP) enzymes, particularly CYP3A4. CYP3A is thought to be involved in the metabolism of more than 50 percent of currently prescribed drugs.2 CYP3A4, which is more abundantly expressed than CYP3A5, accounts for most CYP3A activity in vivo.

The FDA recently cleared the AmpliChip CYP450 Test (Roche), which analyzes blood-derived DNA to detect genetic variations in the activity of cytochrome P450 (CYP) enzymes CYP2D6 and CYP2C19 and determines the metabolizer status of the patient. The test is intended to help guide clinicians in prescribing individualized drug therapy. About 25% of all drugs, including many antidepressants and antipsychotics, are substrates of either CYP2D6 or CYP2C19. The test is being promoted initially to psychiatrists.