Major
Mirtazapine × venlafaxine
Other antidepressants (NaSSA)×SNRI (serotonin-norepinephrine reuptake inhibitor)
Mechanism
'California rocket fuel' augmentation – mirtazapine (5-HT2/3 blocker) + venlafaxine (SNRI). Used in resistant depression. Serotonin syndrome is rare but possible at high doses.
Symptoms
Serotonin syndrome: agitation, confusion, tremor, myoclonus, hyperreflexia. Autonomic features: sweating, tachycardia, fever.
Management
The combination is used for augmentation in resistant depression. Keep doses low: mirtazapine 30 mg, venlafaxine 75–150 mg/day. Monitor blood pressure, pulse, and mental status in the early weeks.
Check the full regimen, not just this pair
Opens the checker with these two drugs prefilled. Add the rest of the regimen and recompute additive risks.