Atomoxetine (Strattera - Lilly) is the first non-stimulant drug to be approved by the FDA for treatment of attention deficit hyperactivity disorder (ADHD). Unlike other drugs approved for use in ADHD, it is not a controlled substance and is approved for use in adults as well as children. Older non-stimulant drugs that have been used to treat ADHD, although not FDA-approved, include the alpha₂-agonist clonidine (Catapres, and others) and the tricyclic antidepressant desipramine (Norpramin, and others) (Medical Letter 1996; 38:109).

Gabapentin (Neurontin - Pfizer), which has been available in the US since 1994, is approved by the FDA only for treatment of partial epilepsy and postherpetic neuralgia, but is widely used off-label for a number of other indications, especially neuropathic pain syndromes. According to one report, among Medicaid recipients in Florida receiving gabapentin, 71% of prescriptions were for chronic pain and 8% for seizures and neuralgia ("The Pink Sheet" February 2, 2004; 66:30).

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.

As the weather becomes warmer, physicians may see more photosensitivity reactions due to systemic or topical drugs, perfumes, cosmetics or sunscreens. Even brief exposure to sunlight in warm or cold weather can cause intense cutaneous reactions in patients with drug-induced photosensitivity, and some patients may continue to be sensitive to sunlight long after stopping use of the offending agent.

Older patients are especially susceptible to drug-induced cognitive impairment. They are more likely to be taking multiple drugs, to have higher blood levels of those drugs because of renal or hepatic dysfunction, and to have pre-existing cognitive problems that make it difficult to detect the role of drugs causing new symptoms or making old ones worse.

Testing for drug use has become increasingly common, not only in health care, but also in drug rehabilitation, in the military, at the workplace, after accidents and in the criminal justice system. Performance-enhancing drugs such as anabolic steroids, growth hormone (Genotropin, and others) and erythropoietin (Procrit, Epogen) are not discussed here.

The FDA recently approved the monoamine oxidase inhibitor (MAOI) selegiline in a transdermal (patch) formulation (Emsam - Bristol-Myers Squibb/Somerset) for treatment of major depressive disorder. Selegiline is also available in an oral formulation (Eldepryl, and others) for treatment of Parkinson's disease.

A selective serotonin reuptake inhibitor (SSRI) is generally used for initial treatment of major depressive disorder (MDD). A serotonin-norepinephrine reuptake inhibitor (SNRI), bupropion (Wellbutrin SR, and others), and mirtazapine (Remeron, and others) are reasonable alternatives. Improvement in symptoms can occur within the first two weeks of treatment with these drugs, but a substantial benefit may not be achieved for 4-8 weeks.

Many commonly used drugs can interfere with sexual function in both men and women, causing loss of libido, interfering with erection or ejaculation in men, and delaying or preventing orgasm in women. Drug-related effects on sexual function may be difficult to distinguish from the effects of depression or disease, but most are reversible when drug use is stopped and sometimes when dosage is decreased. Since many patients are reluctant to talk about sexual difficulties, physicians may wish to ask about the possibility of drug-induced sexual dysfunction, particularly when they have...

Irritable bowel syndrome (IBS) is a common disorder characterized by recurrent abdominal pain and altered bowel habits, often accompanied by bloating. IBS is classified by its predominant bowel symptom: constipation (IBS-C), diarrhea (IBS-D), mixed type (IBS-M), or unclassified (IBS-U). Since the exact cause of IBS is unknown, the goal of treatment is symptom control. Some over-the-counter (OTC) products and prescription drugs for IBS are listed in Tables 1-4. The safety of these drugs during pregnancy and lactation is described in Table 5 (online only).