Venlafaxine (Effexor)
Serotonin-norepinephrine reuptake inhibitor (SNRI) for depression, GAD, social anxiety, and panic disorder. At lower doses primarily serotonergic; norepinephrine reuptake becomes significant above 150 mg/day. Active metabolite desvenlafaxine (marketed separately as Pristiq) is equipotent. Metabolized by CYP2D6. Requires gradual taper, discontinuation syndrome is more severe than most antidepressants due to short half-life.
Projected serum levels — 75 mg, twice daily
Maintenance schedule: 75 mg twice daily (oral).
Loading schedule: 95.5 mg on day 1, then 75 mg twice daily — reaching therapeutic levels sooner.
Modeled steady state after ~1 days: peak ≈ 32.6 mg, trough ≈ 8.9 mg body load. Population-based estimate over 15 days for a 75 mg dose at a 70 kg reference body mass — the interactive app scales curves to your doses, timing, and body mass.
Key facts
- Category
- SNRI
- Route modeled
- Oral
- Model confidence
- inferred
- Half-life
- 5 h
- Common dose
- 75 mg
- Suggested maximum
- 375 mg/day
- Reference dose range
- 37.5–375 mg (single dose)
- Suggested cadence
- twice daily
- Validated against
- 75 mg oral — Cmax 0.23 mg/L at 2 h
Documented interactions
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danger
1P-LSD (1-Propionyl-LSD) + Venlafaxine (Effexor)
1P-LSD (1-Propionyl-LSD) and Venlafaxine (Effexor) both have serotonergic activity. Risk of serotonin syndrome (hyperthermia, rigidity, autonomic instability, altered mental status).
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danger
25I-NBOMe + Venlafaxine (Effexor)
25I-NBOMe and Venlafaxine (Effexor) both have serotonergic activity. Risk of serotonin syndrome (hyperthermia, rigidity, autonomic instability, altered mental status).
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danger
2C-I (2,5-Dimethoxy-4-iodophenethylamine) + Venlafaxine (Effexor)
2C-I (2,5-Dimethoxy-4-iodophenethylamine) and Venlafaxine (Effexor) both have serotonergic activity. Risk of serotonin syndrome (hyperthermia, rigidity, autonomic instability, altered mental status).
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danger
2C-B (4-Bromo-2,5-dimethoxyphenethylamine) + Venlafaxine (Effexor)
2C-B (4-Bromo-2,5-dimethoxyphenethylamine) and Venlafaxine (Effexor) both have serotonergic activity. Risk of serotonin syndrome (hyperthermia, rigidity, autonomic instability, altered mental status).
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danger
4-AcO-DMT (Psilacetin) + Venlafaxine (Effexor)
4-AcO-DMT (Psilacetin) and Venlafaxine (Effexor) both have serotonergic activity. Risk of serotonin syndrome (hyperthermia, rigidity, autonomic instability, altered mental status).
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danger
5-MeO-DMT (5-Methoxy-N,N-dimethyltryptamine) + Venlafaxine (Effexor)
5-MeO-DMT (5-Methoxy-N,N-dimethyltryptamine) and Venlafaxine (Effexor) both have serotonergic activity. Risk of serotonin syndrome (hyperthermia, rigidity, autonomic instability, altered mental…
Serum checks 211 modeled interaction pairings for venlafaxine (effexor) across your whole stack — absorption conflicts, enzyme inhibition, and nutrient depletion included.
Research behind this entry
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Venlafaxine extended release versus placebo and paroxetine in a double-blind, placebo-controlled trial for generalized anxiety disorder
Large RCT demonstrating venlafaxine XR 75-225 mg/day significantly reduced anxiety in GAD patients versus placebo, with response rates of 58-66% at 8 weeks.
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Comparative efficacy and acceptability of 21 antidepressant drugs for the acute treatment of adults with major depressive disorder
Landmark network meta-analysis of 522 trials ranked venlafaxine among the most effective antidepressants, though with lower acceptability than SSRIs due to side effects and discontinuation issues.
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Clinical pharmacokinetics of venlafaxine and O-desmethylvenlafaxine
PK study establishing venlafaxine half-life of 5 hours, active metabolite ODV half-life of 11 hours, and CYP2D6-dependent metabolism with wide interindividual variability in parent-to-metabolite ratio.
3 published studies referenced in the app, each with a plain-language summary.