Amitriptyline Dosing for Migraine Prophylaxis
Amitriptyline should be started at 10-25 mg at bedtime and gradually increased every 3-7 days to a final dose of 30-150 mg/day as tolerated for migraine prophylaxis. 1, 2
Initial Dosing and Titration
- Start with 10-25 mg taken at bedtime
- Increase dose gradually every 3-7 days as tolerated
- Target maintenance dose: 30-150 mg/day (typically given as a single bedtime dose)
- Allow 3-4 months to reach maximal efficacy 2
Dosing Considerations
- Lower starting doses (10 mg) are preferred to minimize side effects
- Bedtime administration helps mitigate sedation side effects
- For children, a standardized dose of 1 mg/kg per day has shown effectiveness 3
- Elderly patients or those sensitive to side effects may benefit from starting at lower doses (10 mg)
Efficacy
- Amitriptyline has demonstrated superior efficacy compared to propranolol in reducing frequency, duration, and severity of migraine attacks 4
- Positive response (≥50% reduction in headache frequency) can be seen in approximately 71% of patients 5
- Efficacy may be observed as early as 8 weeks of treatment 6
- Amitriptyline's effectiveness is likely due to its inhibition of serotonin reuptake and 5-HT2 receptor antagonism 5
Side Effect Management
- Common side effects include dry mouth, constipation, and sedation 1
- Side effects can be minimized by:
- Starting with lower doses
- Administering at bedtime
- Slow titration schedule
- Dose reduction if side effects are intolerable
Monitoring and Follow-up
- Assess response after 4-8 weeks of treatment
- Continue effective treatment for 3-6 months before considering gradual tapering
- Monitor for improvement in headache frequency, severity, and duration
- Track response using a headache diary 2
Clinical Pearls
- Amitriptyline's analgesic effects occur at lower doses than those required for antidepressant effects
- Particularly beneficial for patients with comorbid depression or sleep disturbances
- May be more effective in patients with chronic daily headache compared to episodic migraine 6
- Avoid abrupt discontinuation; taper gradually when stopping treatment
Amitriptyline remains one of the most commonly used and effective medications for migraine prophylaxis despite being an older medication. Its efficacy is well-established, and with appropriate dosing strategies, side effects can be minimized while maximizing therapeutic benefit.