What is the recommended dosing for trazodone (an antidepressant) in the treatment of insomnia?

Trazodone Dosing for Insomnia

For insomnia treatment, trazodone should be dosed at 50-100 mg taken as a single dose approximately one hour before bedtime, with 50 mg being appropriate for most patients initially and 100 mg showing better efficacy for sleep maintenance insomnia. 1, 2

Dosing Recommendations

• Initial dose: 50 mg taken 1 hour before bedtime
• Effective dose range: 50-200 mg for most patients 3
• Elderly patients: Start at lower doses (25-50 mg) due to increased sensitivity and fall risk 1
• Timing: Administer at least 1 hour before bedtime (unlike hypnotics which can be taken immediately before sleep) 4

Clinical Considerations

Mechanism and Efficacy

• Trazodone promotes sleep primarily through antagonism of 5-HT2 serotonin receptors 4
• More effective for sleep maintenance insomnia than sleep onset insomnia 1, 4
• Increases deep sleep duration, which improves subjective sleep quality 4
• Does not cause tolerance or rebound insomnia upon discontinuation 5

Patient-Specific Considerations

1. Primary vs. Secondary Insomnia:

   • Effective for both primary insomnia and secondary insomnia (due to depression, PTSD, dementia) 6
   • Particularly useful when insomnia is comorbid with depression 6

2. Type of Insomnia:

   • For sleep onset insomnia: Consider alternatives like zolpidem (10mg, 5mg for elderly) or zaleplon (10mg) 1
   • For sleep maintenance insomnia: Trazodone is particularly effective 1, 4

3. Special Populations:

   • Elderly: Use lower doses (25-50 mg) due to increased sensitivity 1
   • Patients with respiratory conditions: Use with caution and at lower doses 1
   • Patients with history of substance use: Trazodone may be preferable to scheduled medications 1

Monitoring and Follow-up

• Assess sleep parameters within 2-4 weeks of starting treatment 1
• Monitor for side effects, particularly:
  • Drowsiness (most common side effect) 5, 6
  • Priapism (reported in 12% of patients in one study) 3
  • Daytime sedation 1

Common Pitfalls and Caveats

• Timing errors: Trazodone needs to be administered earlier than hypnotics (at least 1 hour before bedtime) for optimal effect on sleep onset 4
• Dosing errors: The FDA-approved dosing for depression (150-400 mg/day) is higher than what's needed for insomnia (50-100 mg) 7, 6
• Drug interactions: Consider dose reduction when used with strong CYP3A4 inhibitors 7
• Discontinuation: Gradually reduce dosage rather than abrupt discontinuation to avoid withdrawal symptoms 7
• Screening: Screen for bipolar disorder before initiating treatment 7
• MAOI interactions: Allow 14 days between MAOIs and trazodone 7

Trazodone's efficacy for insomnia has been repeatedly demonstrated in clinical studies, with the advantage of improving sleep quality without the tolerance issues associated with traditional hypnotics 6. The side effect profile is generally mild and dose-dependent, with drowsiness being the most commonly reported adverse effect 5, 6.