Selection of an antidepressant: mirtazapine.

The number of antidepressants has expanded dramatically in the last decade as a result of the ability to design psychiatric medications in a rational manner. This paper provides a broad overview of these options while focusing on the most recently approved antidepressant, mirtazapine. The paper discusses the five major features that a physician needs to consider when selecting a medication for a patient: safety, tolerability, efficacy, payment, and simplicity. These five features are summarized by the mnemonic STEPS. The paper also proposes a pharmacologically based classificatory system that divides current antidepressants into eight groups based on the mechanism of action thought to underlie their antidepressant efficacy. Such a classificatory system can serve as an organizing principle for the practicing physician.