Pioglitazone is the third thiazolidinedione ("glitazone") to be marketed in the USA for treatment of type 2 diabetes. Thiazolidinediones decrease resistance to insulin.

View Table: Mechanisms of Drug Interactions

Itraconazole (Sporanox - Janssen), an antifungal triazole, has been approved by the US Food and Drug Administration (FDA) for oral treatment of histoplasmosis and blastomycosis. These two endemic mycoses occur both in normal hosts and in immunocompromised patients, such as those with AIDS (RW Bradsher, Clin Infect Dis, 14:S82, 1992; LJ Wheat, Clin Infect Dis, 14:S91, 1992).

Cetirizine (Zyrtec - Pfizer), a histamine H 1 -receptor antagonist, has been approved by the US Food and Drug Administration for treatment of seasonal allergic rhinitis, perennial allergic rhinitis and chronic idiopathic urticaria in adults and children more than 12 years old.

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.

Zonisamide (Zonegran - Elan Pharma), a sulfonamide chemically unrelated to other antiepileptic drugs, has been approved by the FDA for adjunctive use in adults with partial seizures. Zonisamide has been available in Japan for more than 10 years.

The FDA has approved the marketing of buprenorphine in sublingual tablets (Reckitt Benckiser) both alone (Subutex) and with naloxone (Suboxone) for treatment of opioid dependence. Previously available only for parenteral use in treatment of pain (Buprenex, and others), it offers an alternative to methadone (Dolophine, and others), which is now often abused (New York Times, February 9, 2003; page 1). As a schedule III narcotic, buprenorphine will be subject to fewer prescribing restrictions than a schedule II drug such as methadone (MJ Kreek and FJ Vocci, J Subst Abuse Treat 2002;...

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.

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 has approved artemether-lumefantrine (Coartem - Novartis) for oral treatment of uncomplicated Plasmodium falciparum malaria. It is not approved for prophylaxis. Artemether-lumefantrine is the first artemisinin-based drug approved for use in the US. Artemisinins are Chinese herbal products used worldwide to treat malaria. The intravenous formulation of artesunate, another artemisinin, is available in the US through the CDC.