Mirtazapine Dosing for Appetite Stimulation
The recommended dose of mirtazapine for appetite stimulation is 15-30 mg daily, with 30 mg showing the most evidence for weight gain effects. 1, 2
Evidence-Based Dosing Recommendations
Starting Dose
- Begin with 7.5-15 mg once daily at bedtime
- Lower starting doses (7.5 mg) may be appropriate for elderly patients or those sensitive to sedation 3
- Titrate up to 30 mg daily as needed and tolerated 2
Optimal Therapeutic Dose
- 30 mg daily appears to be the most effective dose for weight gain
- In a retrospective study of patients with Alzheimer's disease, 30 mg daily resulted in weight gain in 77.3% of patients after 3 months (mean gain 1.93 kg) and 82.3% after 6 months (mean gain 2.11 kg) 2
Clinical Considerations
Timeframe for Response
- Initial appetite improvement may be seen within days
- Significant weight gain typically requires 3-6 months of consistent treatment 2
- If no improvement is seen after 4 weeks, consider alternative approaches
Patient Selection
- Most appropriate for patients with:
Monitoring Parameters
- Weight (baseline and at regular intervals)
- Food intake
- Sedation/somnolence
- Mood changes
Efficacy and Limitations
Mirtazapine has demonstrated efficacy for appetite stimulation in several contexts:
- In hospitalized patients, mirtazapine showed numerical improvements in meal intake (average 17.12% increase) 5
- In Alzheimer's disease patients, 30 mg daily resulted in weight gain in over 80% of patients after 6 months 2
- For cancer patients, evidence suggests benefit for nausea control, though appetite stimulation effects are less consistent 6, 3
Common Pitfalls to Avoid
- Excessive sedation: Start with lower doses in elderly or frail patients
- Using in patients with dementia without depression: Guidelines recommend against using appetite stimulants in dementia patients without depression 1
- Inadequate duration: Allow sufficient time (3-6 months) for weight gain effects
- Failure to address underlying causes: Always investigate and treat underlying causes of appetite loss
Alternative Appetite Stimulants
If mirtazapine is ineffective or contraindicated, consider:
- Megestrol acetate (160 mg daily minimum, optimal dose) 1, 4
- Corticosteroids (short-term use only) 1
- Dronabinol (limited evidence in hospitalized patients) 5, 7
Mirtazapine may be particularly useful when depression coexists with appetite loss, as it addresses both conditions simultaneously.