Tca precautions

1. Precautions : TCAs should be used with caution in patients with bipolar disorder, even during their depressed state, because antidepressants may cause a switch to manic behavior. The TCAs have a narrow therapeutic index (for example, five- to sixfold the maximal daily dose of imipramine can be lethal). Depressed patients who are suicidal should be given only limited quantities of these drugs and be monitored closely. The TCAs may exacerbate certain medical conditions, such as unstable angina, benign prostatic hyperplasia, epilepsy, and preexisting arrhythmias. Caution should be exercised with their use in very young or very old patients as well.