Patients with frequent, severe or disabling migraine headaches may benefit from taking a drug to prevent the attacks. Beta-blockers traditionally have been the prophylactic treatment of choice, but in recent years some antiepileptic drugs such as valproate (Depakote, and others) and topiramate (Topamax) have also been used for this indication. Valproate was approved by the FDA for such use in 1996. Now topiramate has also been approved.

View the Comparison Table: Some Oral Anticoagulants for VTE

Erlotinib (Tarceva) is the second oral epidermal growth factor receptor (EGFR) inhibitor to become available in the US for treatment of advanced refractory NSCLC. In clinical trials, erlotinib produced a response rate of only 8.9%, but increased median survival from 4.7 to 6.7 months. Patients who had never smoked and those with EGFR-positive tumors survived longer. Erlotinib is generally well tolerated; diarrhea and rash are the most common adverse effects.

A recent letter to the editor of the Annals of Internal Medicine documented a single case of myopathy apparently due to an interaction between simvastatin (Zocor, and others) and green tea. Since it became available generically, simvastatin has surpassed atorvastatin (Lipitor) as the best selling statin. As such, it is probably the most common cause of statin-induced myopathy, which is often a result of drug interactions.

Paroxetine (Paxil - SmithKline Beecham), a new selective serotonin reuptake inhibitor (SSRI), is now available in the USA. Two other SSRIs, fluoxetine (Prozac - Medical Letter, 30:45, 1988; 32:83, 1990) and sertraline (Zoloft - Medical Letter, 34:47, 1992), were approved previously.

Some commonly used systemic drugs that may cause pulmonary toxicity are listed in the table below. These adverse effects may sometimes be difficult to distinguish from the underlying disease (JAD Cooper, Jr et al, Am Rev Respir Dis, 133:321, 488, 1986). Pulmonary effects that are part of a generalized reaction or are indirect effects of drugs - on respiratory muscles, for example, or on the immune system - are not included here.

Changes caused by one drug in the absorption, distribution, metabolism or excretion of another may lead to a pharmacokinetic adverse drug interaction (DN Juurlink et al, JAMA 2003; 289:1652). Additive drug interactions, such as vasodilation caused by both sildenafil (Viagra) and nitrates, can also have adverse effects.

Tinidazole (Tindamax - Presutti Labs), an oral antiprotozoal drug similar to metronidazole (Flagyl, and others), has been approved by the FDA for treatment of trichomoniasis in adults and for treatment of giardiasis, intestinal amebiasis and amebic liver abcess in adults and children more than 3 years old. Tinidazole has been widely used outside of the US for decades under the trade name Fasigyn (Pfizer).

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.

Dronedarone (Multaq - Sanofi-Aventis) has been approved by the FDA for oral treatment of atrial fibrillation and flutter. Amiodarone (Cordarone, and others) is the most effective drug for this indication, but has considerable toxicity.