Amitriptyline oral

Therapeutic action

Tricyclic antidepressant.

Indications

Due to the numerous and potentially severe adverse effects of amitriptyline, patients should be kept under close surveillance.

• Neuropathic pain.
• Major depression; preferably use selective serotonin re-uptake inhibitors for this indication.

Forms and strengths

• 25 mg tablet.

Dose

Do not exceed 150 mg daily. Reduce the dose by half in older patients.

Duration

• Neuropathic pain: 3 to 6 months after pain relief is obtained. If pain reappears, recommence treatment.
• Major depression: at least 9 months. Discontinue treatment gradually over 4 weeks. If signs of relapse or withdrawal occur, increase the dose then decrease it more gradually.

Contra-indications, adverse effects, precautions

• Do not administer to patients with recent myocardial infarction, arrhythmia, closed-angle glaucoma, or prostate disorders.
• Administer with caution and carefully monitor use in older patients and in patients with epilepsy, chronic constipation, renal or hepatic impairment, history of bipolar disorders, and suicidal ideation.
• May cause drowsiness, orthostatic hypotension, and sexual dysfunction.
• May cause anticholinergic effects including dry mouth, constipation, blurred vision, tachycardia, and disorders of micturition. Discontinue treatment in the event of severe reactions such as confusional state, urinary retention, or cardiac rhythm disorders.
• Administer with caution and monitor combinations with CNS depressants, drugs known to have anticholinergic effects, drugs which lower the seizure threshold, serotonergic drugs, and anti-hypertensive drugs.
• Avoid alcohol during treatment.
• Pregnancy: re-evaluate whether treatment is still necessary. If continued, maintain amitriptyline at effective dose and observe the neonate during the first few days if the mother was under treatment in the 3rd trimester. If treatment for major depression starts during pregnancy, preferably use sertraline.
• Breast-feeding: monitor the child for excessive somnolence.