Home › Compound Library › Trazodone (Desyrel)

Trazodone (Desyrel)

SSRIprescriptionoral · predicted

Serotonin antagonist and reuptake inhibitor (SARI) used at low doses for insomnia and higher doses for depression. Biphasic elimination. Active metabolite mCPP is formed via CYP3A4. Common starting dose for insomnia is 25-50 mg at bedtime.

Projected serum levels — 50 mg, once daily

Trazodone (Desyrel)
Trazodone (Desyrel) modeled serum levels, 50 mg once daily over 15 days Population-based pharmacokinetic estimate. Steady state reached after approximately 2 days. 0 25 50 75 100 Day 0 Day 4 Day 8 Day 11 Day 15 Time on a regular schedule ≈ steady state · day 2
Trazodone (Desyrel) modeled serum levels with a loading dose of 74.3 mg, then 50 mg once daily The first dose is larger so levels approach steady state faster. 0 25 50 75 100 Day 0 Day 4 Day 8 Day 11 Day 15 Time on a regular schedule

Maintenance schedule: 50 mg once daily (oral).

Loading schedule: 74.3 mg on day 1, then 50 mg once daily — reaching therapeutic levels sooner.

Modeled steady state after ~2 days: peak ≈ 52.0 mg, trough ≈ 19.5 mg body load. Population-based estimate over 15 days for a 50 mg dose at a 70 kg reference body mass — the interactive app scales curves to your doses, timing, and body mass.

Key facts

Category
SSRI
Route modeled
Oral
Model confidence
predicted
Half-life
7 h
Common dose
50 mg
Suggested maximum
400 mg/day
Reference dose range
25–400 mg (single dose)
Suggested cadence
once daily
Validated against
150 mg oral — Cmax 1.6 mg/L at 1.5 h

Documented interactions

  • contraindicated
    Clarithromycin (Biaxin) + Trazodone (Desyrel) CYP inhibition

    Clarithromycin (Biaxin) mechanism_based of CYP3A4 predicted to change Trazodone (Desyrel) AUC by ~5.26x

  • contraindicated
    Diltiazem + Trazodone (Desyrel) CYP inhibition

    Diltiazem mechanism_based of CYP3A4 predicted to change Trazodone (Desyrel) AUC by ~5.26x

  • contraindicated
    Efavirenz (Sustiva) + Trazodone (Desyrel) CYP induction

    Efavirenz (Sustiva) inducer of CYP3A4 predicted to change Trazodone (Desyrel) AUC by ~0.14x

  • contraindicated
    Grapefruit (whole fruit) + Trazodone (Desyrel) CYP inhibition

    Grapefruit (whole fruit) mechanism_based of CYP3A4 predicted to change Trazodone (Desyrel) AUC by ~5.26x

  • contraindicated
    Grapefruit Juice + Trazodone (Desyrel) CYP inhibition

    Grapefruit Juice mechanism_based of CYP3A4 predicted to change Trazodone (Desyrel) AUC by ~5.26x

  • contraindicated
    Paxlovid (Nirmatrelvir/Ritonavir) + Trazodone (Desyrel) CYP inhibition

    Paxlovid (Nirmatrelvir/Ritonavir) mechanism_based of CYP3A4 predicted to change Trazodone (Desyrel) AUC by ~5.26x

Serum checks 177 modeled interaction pairings for trazodone (desyrel) across your whole stack — absorption conflicts, enzyme inhibition, and nutrient depletion included.

Research behind this entry

  1. Trazodone for insomnia: a systematic review Jaffer KY et al. · Innovations in Clinical Neuroscience, 2017 DOI

    Systematic review of 45 studies finding 95.5% concluded trazodone was effective for insomnia, though most evidence was in populations with comorbid conditions rather than primary insomnia.

  2. Trazodone for the treatment of insomnia: a meta-analysis of randomized placebo-controlled trials Yi XY et al. · Sleep Medicine, 2018 DOI

    Meta-analysis of 7 RCTs (429 patients) confirming trazodone significantly improved total sleep time, sleep efficiency, and subjective sleep quality compared to placebo in insomnia.

  3. Rediscovering trazodone for the treatment of major depressive disorder Stahl SM · CNS Spectrums, 2009 DOI

    Review of trazodone pharmacology explaining its multimodal mechanism (5-HT2A antagonism, SERT inhibition, histamine antagonism) and rationale for dual use in depression and insomnia.

3 published studies referenced in the app, each with a plain-language summary.