The short answer
Ask about passionflower before combining it with mirtazapine, especially if alertness is already affected. Some guidance warns about driving impairment, but small human trials did not show extra sedation with the tested preparations.
What this answer covers
Oral Passiflora incarnata herb preparations; not passionfruit or other Passiflora species.
- Supplement or preparation
- Passiflora incarnata
- Medication ingredient
- mirtazapine
Why alertness deserves review
Mirtazapine can impair thinking and motor skills. The passionflower monograph also cautions about driving, making symptoms and activities relevant to the decision.
Human studies were not uniformly sedating
Two small perioperative studies found anxiety benefit without a significant sedation or psychomotor difference for their tested products. They did not combine passionflower with mirtazapine.
No reported interaction is not a tested clearance
The monograph lists no reported interactions. That does not establish that concurrent mirtazapine use has been studied or that a fixed time gap prevents impairment.
Watch for impaired alertness
Mirtazapine can affect alertness and coordination. Avoid driving if affected and contact the prescriber if added sleepiness, confusion or unsteadiness appears after a new product. Severe confusion, fainting or inability to wake needs urgent assessment.
Evidence and practical considerations
Side effects & toxicity
Conditional alertness review, with exact-pair sedation magnitude unestablished and negative standalone findings retained.
- Exact scope
- Oral Passiflora incarnata herb preparations; not passionfruit or other Passiflora species. with Exact oral mirtazapine tablets and orally disintegrating tablets. Exact oral mirtazapine in Remeron and RemeronSolTab; manufacturer label covers both. No equivalence to unrelated mirtazapine salts or other antidepressants inferred.
- Medication form and route
- oral
- Timing or duration
- Source-specific single-dose, repeated-dose and observational exposures distinguished.
What remains uncertain
- No mirtazapine co-use trial; perioperative products and traditional-use guidance do not establish all-extract effects.
Factors that may matter: preparation and plant part; clinical indication; dose; other medicines; baseline alertness.
Read the supporting source summaries
Source 1: current product label
dailymed.nlm.nih.gov · Source check Sep 10, 2026
Population: People prescribed oral mirtazapine.
Exact label names tryptophan and St John’s wort in serotonin warnings; CYP3A induction/inhibition may affect levels. Drowsiness and cognitive/motor impairment occur.
How this applies: Exact oral mirtazapine in Remeron and RemeronSolTab; manufacturer label covers both. No equivalence to unrelated mirtazapine salts or other antidepressants inferred.
No universal supplement interval, event rate or preparation equivalence established. Original label distinguishes warnings from measured pair-specific results.
Source 2: official guidance
ema.europa.eu · Source check Sep 10, 2026
Population: People considering the specified supplement.
Traditional sleep-aid use; may impair driving. Section 4.5 lists no reported interactions.
How this applies: Preparation-specific original evidence; no untested antidepressant or route transfer.
Traditional-use monograph, not a mirtazapine trial. No reported interaction is not proof of safety.
Source 3: randomized placebo-controlled trial
pubmed.ncbi.nlm.nih.gov · Source check Sep 10, 2026
Population: 60 adults undergoing ambulatory surgery.
Anxiety decreased, but sedation and psychomotor recovery were similar between groups.
How this applies: Preparation-specific original evidence; no untested antidepressant or route transfer.
Short perioperative exposure to one product, no mirtazapine; does not establish chronic combination safety.
Source 4: randomized placebo-controlled trial
pubmed.ncbi.nlm.nih.gov · Source check Sep 10, 2026
Population: 60 adults aged 25-55 undergoing spinal anesthesia.
No significant group differences in sedation, psychomotor function, hemodynamics or side effects.
How this applies: Preparation-specific original evidence; no untested antidepressant or route transfer.
Selected perioperative population without mirtazapine; not proof that all preparations lack impairment.
Research assessment: · Open full citations ↗
Review and change history
- Publication status
- Published research summary
- Clinical review
- Not yet recorded
| Date | Update |
|---|---|
| Article prepared | |
| Current exact available claims adjudicated using original captures and explicit identity and comparator limits. | |
| Research summary published |
Article revision: 07d88423494cf46d
This guide brings together the evidence records used by our interaction checker. Each finding retains its own preparation limits, research date, and source summaries.
Full citations require verification. Reading this answer and the source summaries does not.
Taking other supplements or medications?
Use the checker to explore your other combinations. Ask a pharmacist to review the exact products, amounts and medical conditions in your complete list.
Open the interaction checkerInformation, not medical advice. Do not change prescribed treatment based on this guide.