The most common clinical mistake leading to an unsuccessful trial of an antidepressant drug is the use of too low a dosage for too short a time. Unless adverse events prevent it, a drug trial of adequate dosage can be considered unsuccessful if the patient does not respond favorably in four weeks. Tricyclic drugs may be lethal when taken in overdose levels.
Antidepressants do have sexual adverse effects.
Almost all the antidepressants, except bupropion, have been associated with decreased libido, erectile dysfunction, or anorgasmia. The serotonergic drugs are probably more closely associated with sexual adverse effects than are the noradrenergic compounds. Although that adverse interaction can be avoided by the patient's following simple dietary guidelines, the potentially life- threatening nature of a hypertensive crisis and the need for dietary restrictions limit the acceptability of MAOIs. Antidepressants alone are not effective in the treatment of major depressive episodes with psychotic features. The usual practice, however, is to use a combination of an antidepressant and an antipychotic.