Appropriate Dosage of Trazodone for Treating Depression
The appropriate dosage of trazodone for treating depression is 150-300 mg/day in divided doses, with a maximum dose of 400 mg/day for outpatients and 600 mg/day for inpatients. 1
Initial Dosing and Titration
- Starting dose: 150 mg/day in divided doses 1
- Titration: Increase gradually by 50 mg/day every 3-4 days based on clinical response and tolerance 1
- Administration: Take shortly after a meal or light snack to improve absorption 1
- Timing: A major portion of the daily dose may be administered at bedtime if drowsiness occurs 1
Dosage Considerations by Patient Population
Standard Adult Patients
- Initial dose: 150 mg/day in divided doses
- Target therapeutic range: 150-300 mg/day
- Maximum outpatient dose: 400 mg/day
- Maximum inpatient dose: 600 mg/day 1
Elderly Patients
- Lower starting doses recommended
- Maximum dose: 300-400 mg/day 2, 3
- Monitor closely for orthostatic hypotension 2
Efficacy Considerations
Trazodone has demonstrated comparable antidepressant activity to other antidepressant classes:
- Similar efficacy to tricyclic antidepressants (TCAs)
- Comparable results to selective serotonin reuptake inhibitors (SSRIs)
- Equivalent outcomes to serotonin-norepinephrine reuptake inhibitors (SNRIs) 4
The antidepressant effect of trazodone is dose-dependent:
- Doses below 150 mg/day are generally insufficient for full antidepressant effect
- Doses of 150-300 mg/day are typically required for adequate depression treatment 5
- Lower doses (25-100 mg) may be used for insomnia but are subtherapeutic for depression 2
Safety and Monitoring
Common Side Effects
- Drowsiness/sedation (most common)
- Headache
- Dizziness
- Dry mouth 4
Serious Adverse Effects (Rare but Important)
- Orthostatic hypotension (particularly in elderly or those with heart disease)
- QT interval prolongation
- Cardiac arrhythmias
- Priapism (rare but requires immediate medical attention) 4, 6
Special Considerations
- Drug Interactions: Consider dose reduction when used with strong CYP3A4 inhibitors 1
- Bipolar Disorder: Screen for bipolar disorder before initiating treatment 1
- Discontinuation: Gradually reduce dosage rather than stopping abruptly 1
- MAOIs: Allow at least 14 days between discontinuing MAOIs and starting trazodone, and vice versa 1
Practical Administration Tips
- Tablets can be swallowed whole or broken along the score line 1
- Taking with food reduces gastrointestinal side effects 1
- If sedation is problematic, administer a larger portion of the dose at bedtime 1
- Once adequate response is achieved, dosage may be gradually reduced with subsequent adjustments based on therapeutic response 1
Trazodone's unique pharmacological profile as a serotonin receptor antagonist and reuptake inhibitor (SARI) makes it particularly useful for patients with depression who also experience insomnia, as it avoids the sleep disturbances often seen with SSRIs 5, 6.