Are psychotropic drugs at therapeutic levels a concern for cardiologists?

To review the cardiovascular effects of psychotropic drugs when used in therapeutic doses and to assess their clinical relevance for cardiologists. Information on newer psychopharmacological agents is also presented.

MEDLINE was used to search the relevant English language medical literature over the past five years. Standard texts and selected earlier references were also used. Input was obtained from local experts.

Many antipsychotics and antidepressants have the potential for causing malignant ventricular arrhythmias and cardiac conduction disturbances. Postural hypotension is also a common side effect with important associated morbidity. The effects of psychotropic drugs on myocardial contractile properties are not significant at therapeutic dose levels. Older agents, such as phenothiazines, tricyclic antidepressants and monoamine oxidase inhibitors, are responsible for most of the reported adverse cardiovascular effects of psychotropic drugs. Selective serotonin reuptake inhibitors are a newer class of antidepressants that are free from significant direct cardiovascular adverse effects; however, if combined with other agents such as the monoamine oxidase inhibitors, they can cause cardiovascular collapse as part of a potentially fatal 'serotonin syndrome'. These newer agents can also exaggerate the actions of certain cardiac drugs through effects on their metabolism by inhibition of cytochrome P450 isoenzymes.

The adverse cardiovascular effects of psychotropic medications in therapeutic doses are a valid concern for cardiologists. Familiarity with these drugs and their interactions is essential to avoid important undesired reactions with potential fatal consequences.