Tricyclics are less commonly prescribed now due to the development of newer antidepressants which are considered safer. Tricyclics work by blocking the re-uptake absorption of two neurotransmitters - norepinephrine and serotonin in the brain.

Side effects of Tricyclics include increased heart rate,blurred vision, dizziness, confusion, constipation, urinary retention, drowsiness, and sexual dysfunction.

Tricyclics can be highly toxic at high doses. However, they are still prescribed in serious cases because of their efficacy.