What is the typical adult dose of trazodone (an antidepressant medication) for depression and insomnia?

Adult Dose of Trazodone

For depression, start trazodone at 150 mg/day in divided doses and increase by 50 mg every 3-4 days up to 400 mg/day for outpatients (600 mg/day for inpatients), taken shortly after meals. 1

Depression Treatment Dosing

Initial Dosing

• Begin at 150 mg/day in divided doses 1
• Administer shortly after a meal or light snack to optimize absorption 1
• If drowsiness occurs, shift the major portion of the daily dose to bedtime 1

Dose Titration

• Increase by 50 mg/day every 3-4 days based on clinical response and tolerability 1
• Outpatients: maximum 400 mg/day in divided doses 1
• Inpatients (more severely depressed): up to 600 mg/day in divided doses 1

Alternative Dosing Strategy

• Single nighttime dosing (150-300 mg at bedtime) is equally effective as divided doses for depression and produces better sleep with less daytime drowsiness during initial treatment. 2
• This approach leverages trazodone's 3-9 hour half-life and is particularly useful when insomnia accompanies depression 2

Insomnia Treatment Dosing (Off-Label)

Low-Dose Regimen

• The American Academy of Family Medicine recommends 25 mg at bedtime initially for insomnia, with a maximum of 200-400 mg/day in divided doses if needed 3
• Lower doses (25-50 mg) are typically used for insomnia, which are below the therapeutic antidepressant range 4

Important Caveat About Insomnia Use

• The American Academy of Sleep Medicine recommends against using trazodone for primary insomnia based on trials showing modest improvements that do not outweigh potential harms. 3, 4
• Trazodone is considered only a third-line agent for insomnia, after cognitive behavioral therapy and benzodiazepine receptor agonists fail 4
• It may be more appropriate when comorbid depression or anxiety is present 4

Special Populations

Elderly Patients

• Lower starting doses are recommended due to increased risk of side effects, particularly orthostatic hypotension 3, 5
• Maximum tolerated doses are typically 300-400 mg/day in elderly patients 5

Administration Details

Tablet Administration

• Tablets can be swallowed whole or broken along the score line 1
• Take shortly after meals to reduce side effects and optimize absorption 1

Drug Interactions Requiring Dose Adjustment

• With strong CYP3A4 inhibitors: Consider reducing dose based on tolerability 1
• With strong CYP3A4 inducers: Consider increasing dose based on therapeutic response 1

Safety Considerations

Contraindications and Precautions

• Screen for bipolar disorder, mania, or hypomania before initiating treatment 1
• Allow at least 14 days between discontinuing an MAOI and starting trazodone (and vice versa) 1
• Use with caution in patients with premature ventricular contractions 3
• Monitor for orthostatic hypotension, especially in cardiovascular disease and elderly patients 6

Discontinuation

• Taper gradually over 10-14 days rather than stopping abruptly to limit withdrawal symptoms 3, 1
• Reduce dosage gradually once adequate response is achieved 1

Common Adverse Effects

• Most common: somnolence, headache, dizziness, and dry mouth 6
• Dose-dependent drowsiness is the most frequent side effect 7
• Rare but serious: priapism, cardiac arrhythmias, QT prolongation 6, 5
• Notably lower anticholinergic and cardiovascular effects compared to tricyclic antidepressants 5