Many fermented foods contain tyramine as a byproduct formed by the bacterial breakdown of the amino acid tyrosine; it can also be formed by para-hydroxylation of phenylethylamine or dehydroxylation of DOPA and dopamine. Tyramine and some other amines found in food can cause hypertensive reactions in patients taking monoamine oxidase (MAO)inhibitors.

In the February 2003 update of the Adverse Drug Interactions Program and in the Handbook of Adverse Drug Interactions 2003, the potentially lethal interaction between selective serotonin reuptake inhibitors (SSRIs) and monoamine oxidase inhibitors (MAOIs) was inadvertently omitted for citalopram (Celexa) and escitalopram (Lexapro). This interaction could occur with any SSRI.

Alprazolam (Xanax - Upjohn), a triazolobenzodiazepine previously available in the USA for treatment of anxiety (Medical Letter 24:41, 1982), was recently approved by the US Food and Drug Administration (FDA) for treatment of panic disorder, with or without agoraphobia. According to one report, alprazolam was the fifth most widely prescribed drug in the USA last year (American Medical News, March 4, 1991, page 4).

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.

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).

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).

Sibutramine hydrochlorid monohydreate (Meridia - Knoll), which is structurally related to amphetamine, has been approved by the FDA for treatment of obesity. It is classified by the Drug Enforcement Agency (DEA) as a schedule IV controlled substance.

Duloxetine hydrochloride (Cymbalta - Lilly), a selective serotonin and norepinephrine reuptake inhibitor (SNRI) available for treatment of depression, has also been approved by the FDA for treatment of neuropathic pain associated with diabetic peripheral neuropathy (DPN). Duloxetine is one of two drugs approved specifically for management of neuropathic pain due to diabetes; the other, pregabalin (Lyrica - Pfizer), will be marketed soon and will be reviewed in the next issue of The Medical Letter.

Altretamine (Hexalen - US Bioscience; Hexastat - Rh ne-Poulenc in Canada), formerly known only by its chemical name, hexamethylmelamine, was recently approved by the US Food and Drug Administration as a single agent for palliative oral treatment of persistent or recurrent ovarian cancer.

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?