Nortriptyline

How it works

It inhibits the reuptake of noradrenaline and, to a lesser extent, serotonin at central synapses, increasing their availability; it is the active metabolite of amitriptyline.

Prescribing in practice

• Tricyclic antidepressants are dangerous in overdose, causing cardiac arrhythmias and seizures, so caution is needed in patients at risk of suicide and quantities supplied should be considered carefully.
• It has anticholinergic and cardiac effects and should be used with caution in the elderly and in those with cardiovascular disease, urinary retention, glaucoma or epilepsy.
• Avoid concomitant use with MAO inhibitors and use serotonergic combinations cautiously because of the risk of serotonin syndrome.

Monitoring

Monitor mood and suicidal ideation, cardiovascular status and anticholinergic side effects, with ECG considered where cardiac risk factors are present.

Counselling the patient

• This medicine may cause drowsiness, dry mouth or constipation, particularly when starting.
• It can take a few weeks to feel the full benefit, so keep taking it as prescribed.
• Do not stop abruptly; your prescriber will advise on reducing the dose gradually.

Evidence & guidelines

Nortriptyline is a long-established tricyclic antidepressant, and the dangers of tricyclics in overdose are well documented and reflected in NICE depression guidance.