Since the introduction of fluoxetine (Prozac - Medical Letter, 30:45, 1988), bupropion (Wellbutrin - Medical Letter, 31:97, 1989), sertraline (Zoloft - Medical Letter, 34:47, 1992) and paroxetine (Paxil - this issue), the choice of an antidepressant has become more difficult. Should these widely prescribed new drugs replace tricyclic antidepressants such as amitriptyline (Elavil, and others), imipramine (Tofranil, and others), or nortriptyline (Aventyl, and others) for treatment of most patients with depression?

Pentosan polysulfate sodium (Elmiron - Baker Norton), a semi-synthetic mucopolysaccharide structurally similar to heparin, has been approved by the US Food and Drug Administration for oral treatment of interstitial cystitis.

The physiologic changes that occur with aging can affect the pharmacokinetics and pharmacodynamics of many prescription and over-the-counter drugs, increasing the likelihood of adverse effects.

S-adenosyl-methionine (SAM; SAMe; ademetionine; adomet), an endogenous compound synthesized from methionine and adenosine-triphosphate (ATP), has been marketed in stores and on the internet as a dietary supplement to promote "emotional well being."

Three benzodiazepines and 16 other compounds are marketed in the USA for treatment of insomnia. Many authorities believe that insomnia is overdiagnosed and overtreated (MK Erman, ed, Sleep Disorders, Psychiatr Clin North Am, Volume 10, Dec 1987).

Bupropion (Wellbutrin - Burroughs Wellcome) was recently marketed in the USA for treatment of depression. First approved by the Food and Drug Administration in late 1985, the drug was withdrawn from the market in early 1986 because of a high incidence of seizures in one study.

Sertraline (Zoloft - Roerig), a serotonin reuptake inhibitor, was recently approved for marketing by the US Food and Drug Administration for treatment of depression. Another serotonin reuptake inhibitor, fluoxetine (Prozac), is prescribed more frequently in the USA than any other antidepressant (Medical Letter, 32:83, 1990).

Venlafaxine hydrochloride (Effexor - Wyeth-Ayerst) was recently approved by the US Food and Drug Administration for treatment of depression. An aminomethyl-benzyl- cyclohexanol, it is chemically related to bupropion (Wellbutrin).

Even though its effectiveness has not been established, many patients take St. John's Wort (Hypericum perforatum), an over-the-counter herbal extract, to treat symptoms of depression, often without the knowledge of their physicians. Recent reports indicate that St. John's wort interacts adversely with a number of drugs.

Fluoxetine (Prozac - Dista), a phenylpropylamide, is the first serotonin-reuptake blocker introduced in the USA for treatment of . It is being promoted as causing fewer adverse effects than other antidepressants. Claims of greater safety and patient tolerability have often been made for new non-tricyclic antidepressants in recent years, but unpredicted adverse effects have emerged with widespread use, including priapism with trazodone (Desyrel - Medical Letter, 26:35, 1984) and fatal hemolytic anemia with nomifensine (Merital - Medical Letter, 27:73, 1985).