Tricyclic Antidepressants (TCAs)
Examples: amitryptiline, clomipramine, dothiepin, imipramine, lofepramine
The nerve cells normally recycle serotonin and norepinephrine by soaking it back up again. The majority of TCAs work by stopping (inhibiting) this re-uptake of serotonin and norepinephrine. As serotonin and norepinephrine is not soaked up again, more will be present to pass on messages to nerve cells nearby.
Common side effects, as associated with the receptor profiles:
- Anticholinergic: dry mouth, blurred vision, urinary retention, constipation, drowsiness, confusion.
- Adrenergic antagonism: drowsiness, postural hypotension, tachycardia, sexual dysfunction.
- Antihistaminergic: drowsiness, weight gain.
- 5HT2 antagonism: anxiolytic, reduced sexual dysfunction, sedation.
- Well-established efficacy
- Possibly more effective in severe depression
- Toxicity in overdose
- Less well-tolerated than SSRIs
- Lower seizure threshold
- Slow cardiac conduction