What is the proper dosage and administration of Trazodone (antidepressant) 150mg for managing depression or insomnia?

Trazodone 150mg Dosing and Administration

For depression, trazodone 150mg/day in divided doses is the FDA-approved starting dose, which can be increased by 50mg every 3-4 days up to 400mg/day for outpatients; for insomnia, trazodone is NOT recommended as first-line therapy and should only be considered after FDA-approved hypnotics have failed, particularly when comorbid depression is present. 1, 2

For Major Depressive Disorder

Initial Dosing Strategy

• Start at 150mg/day in divided doses as the FDA-approved initial dose 1
• The dose should be initiated low and increased gradually while monitoring clinical response and tolerability 1
• If drowsiness occurs, administer the major portion of the daily dose at bedtime or reduce the total dose 1

Dose Titration

• Increase by 50mg/day every 3-4 days based on therapeutic response 1
• Outpatients: Maximum dose typically should not exceed 400mg/day in divided doses 1
• Inpatients (more severely depressed): May receive up to 600mg/day in divided doses 1
• Once adequate response is achieved, gradually reduce dosage with subsequent adjustments based on therapeutic response 1

Alternative Dosing Regimen

• Single nighttime dosing at 150mg (weighted predominantly at bedtime) is equally effective as divided doses and produces better sleep with less daytime drowsiness at treatment onset 3
• This can be increased to 200-300mg for full antidepressant efficacy 3
• The 3-9 hour half-life of trazodone favors bedtime-weighted dosing 3

Administration Instructions

• Take shortly after a meal or light snack to optimize absorption 1
• Tablets can be swallowed whole or broken along the score line 1

For Insomnia (Off-Label Use)

Critical Positioning in Treatment Algorithm

• Trazodone is a third-line agent for insomnia, only after benzodiazepine receptor agonists and ramelteon have failed 2, 4
• The American Academy of Sleep Medicine recommends AGAINST using trazodone for sleep onset or sleep maintenance insomnia in adults based on 50mg dose trials 2
• The benefits do not outweigh potential harms according to current guidelines 2

When Trazodone May Be Appropriate for Insomnia

• Comorbid depression with insomnia: Trazodone becomes a reasonable first-line adjunct option 5, 4
• Start at 50mg at bedtime for insomnia with depression 5
• Note: Low doses (25-50mg) used for insomnia are inadequate for treating major depression and require combination with a full-dose antidepressant 2

Preferred Alternatives for Primary Insomnia

First try these FDA-approved options before trazodone:

• Cognitive Behavioral Therapy for Insomnia (CBT-I) as initial treatment 2, 4
• Second-line pharmacologic options: Eszopiclone 2-3mg, zolpidem 10mg, zaleplon 10mg, ramelteon 8mg, temazepam 15mg, or suvorexant 2
• Doxepin 3-6mg specifically for sleep maintenance insomnia 2

Special Populations and Safety Considerations

Elderly Patients

• Consider dose reduction due to increased sensitivity to side effects 2
• Trazodone has minimal anticholinergic effects compared to tricyclics, making it safer than amitriptyline in elderly patients 5
• Caution regarding orthostatic hypotension risk 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: At least 14 days must elapse between discontinuing an MAOI and starting trazodone, and vice versa 1

Contraindications and Precautions

• Avoid in pregnancy and nursing 2
• Exercise caution with compromised respiratory function, hepatic or heart failure 2
• Screen for bipolar disorder before initiating treatment (personal or family history of bipolar disorder, mania, or hypomania) 1
• Monitor for QT interval prolongation and cardiac arrhythmias 6
• Rare but serious: priapism (led to treatment discontinuation in clinical studies) 2, 6

Monitoring and Follow-Up Requirements

Initial Phase

• Follow-up every few weeks initially to assess effectiveness, side effects, and ongoing medication need 4, 2
• Track sleep patterns with sleep logs if used for insomnia 5
• Monitor for complex sleep behaviors and next-morning impairment 5

Ongoing Management

• Use the lowest effective maintenance dose 4, 2
• Gradually taper medication when conditions allow rather than abrupt discontinuation 1
• Consider tapering after 3-4 weeks if insomnia improves 5

Patient Education Essentials

Must Discuss with Patients

• Treatment goals and expectations 4
• Safety concerns and potential side effects (most common: drowsiness, headache, dizziness, dry mouth) 6, 4
• Availability of cognitive-behavioral treatments 2
• Risk of daytime drowsiness and psychomotor impairment 2
• Potential for dosage escalation and rebound insomnia 4
• Allow appropriate sleep time after taking medication 2

Common Pitfalls to Avoid

• Do NOT use trazodone as first-line therapy for primary insomnia 2
• Do NOT prescribe without attempting CBT-I or FDA-approved hypnotics first for primary insomnia 2
• Do NOT combine two sedating antidepressants 2
• Do NOT use over-the-counter antihistamines or herbal supplements (valerian, melatonin) as alternatives—they lack efficacy and safety data 4, 5
• Do NOT use older agents including barbiturates and chloral hydrate 4, 2
• Do NOT stop abruptly—taper gradually to avoid withdrawal symptoms 1