What is the recommended dosing for trazodone (antidepressant) for patients with insomnia or depression?

Trazodone Dosing for Insomnia and Depression

For depression, trazodone should be started at 150 mg/day in divided doses and may be increased to a maximum of 400 mg/day for outpatients or 600 mg/day for inpatients; for insomnia, a lower dose of 25-50 mg at bedtime is typically effective. 1

Dosing for Depression

Trazodone is FDA-approved for the treatment of major depressive disorder with the following dosing recommendations:

• Initial dose: 150 mg/day in divided doses 1
• Dose titration: Increase by 50 mg/day every 3-4 days based on response and tolerability 1
• Maximum dose:
  • Outpatients: 400 mg/day in divided doses 1
  • Inpatients: 600 mg/day in divided doses 1

Administration considerations:

• Take shortly after a meal or light snack 1
• Can be swallowed whole or broken along score line 1
• A major portion of the daily dose may be administered at bedtime to manage drowsiness 1

Dosing for Insomnia (Off-Label Use)

Although not FDA-approved for insomnia, trazodone is widely prescribed for this indication:

• Initial dose: 25 mg at bedtime 2
• Effective dose range: 25-100 mg at bedtime 3
• Maximum dose for insomnia: 200-400 mg per day in divided doses 2

Research shows that lower doses (25-75 mg) are often more effective for insomnia than higher doses, with the highest percentage of responders at the minimum dose of 25 mg 4.

Clinical Considerations

For Depression

• Trazodone requires 4-8 weeks for a full therapeutic trial 2
• Dose increases should use increments of initial dose every 5-7 days 2
• After 9 months, consider dose reduction to reassess need for medication 2
• Discontinuation should occur gradually over 10-14 days to limit withdrawal symptoms 2

For Insomnia

• Low-dose trazodone (≤100 mg/day) has demonstrated efficacy for both primary insomnia and secondary insomnia related to depression and other conditions 3
• Side effects are dose-dependent, with drowsiness being most common 3
• For patients with primarily sleep onset issues, alternative agents like ramelteon or low-dose Z-drugs may be more appropriate 5

Special Populations

• Elderly patients: Start at lower doses due to increased risk of side effects
• Patients with cardiovascular disease: Use with caution due to risk of orthostatic hypotension 2

Side Effects and Monitoring

Common side effects include:

• Somnolence (most common)
• Headache
• Dizziness
• Xerostomia (dry mouth) 6

Serious but less common side effects:

• Orthostatic hypotension (especially in elderly or those with cardiovascular disease)
• QT interval prolongation
• Cardiac arrhythmias
• Rare episodes of priapism 6

Drug Interactions

• Strong CYP3A4 inhibitors: Consider reducing trazodone dose based on tolerability 1
• Strong CYP3A4 inducers: Consider increasing trazodone dose based on therapeutic response 1
• MAOIs: Allow at least 14 days between discontinuing an MAOI and starting trazodone, and vice versa 1

Trazodone's efficacy for depression is comparable to other antidepressants, with the added benefit of improving insomnia symptoms without the sexual dysfunction or weight gain often associated with SSRIs 6, 7.