The short answer
Ask the prescriber before combining St John’s wort with imipramine. A serotonin-related precaution is reasonable, but trials comparing them as alternatives do not establish safe co-use or reduced imipramine absorption.
What this answer covers
Oral Hypericum perforatum and imipramine; UK hydrochloride solution warning is pharmacodynamic context, not a formulation dose bridge.
- Supplement or preparation
- Hypericum perforatum
- Medication ingredient
- imipramine
Why review is appropriate
NCCIH warns about serotonin-related effects with certain antidepressant combinations. The UK imipramine hydrochloride oral-solution information cautions about other serotonergic agents; it does not quantify this specific combination.
The major trial compared alternatives
A trial in 324 people compared St John’s wort with imipramine in separate groups. Similar improvement and fewer herb adverse events do not mean taking both is safe.
Reduced absorption is a separate claim
The comparison did not measure imipramine exposure during herb co-use. Do not assume that St John’s wort makes imipramine weaker or that separating doses solves the concern.
Plan changes with the prescriber
Bring the exact extract and dose, and report new agitation, confusion, sweating or muscle symptoms promptly. Do not adjust imipramine yourself.
Evidence and practical considerations
Side effects & toxicity
Conditional serotonin review is supported; exact-pair reduced absorption or loss of effectiveness remains insufficiently established.
- Exact scope
- Oral Hypericum perforatum and imipramine; UK hydrochloride solution warning is pharmacodynamic context, not a formulation dose bridge. with Exact oral imipramine hydrochloride tablets. RxNorm IN 5691/PIN 150816 hydrochloride; pamoate capsule is not assumed the same tested formulation. Desipramine metabolite evidence is distinguished from directly prescribed imipramine.
- Medication form and route
- oral
- Timing or duration
- Source-specific single-dose, repeated-dose and observational exposures distinguished.
What remains uncertain
- Current US tablet label does not name SJW; UK oral ingredient label gives a general serotonergic warning. Comparator study is not co-use.
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 imipramine.
Exact label warns about anticholinergic and sympathomimetic co-use, alcohol-related CNS effects and MAOI combinations. It does not explicitly name tryptophan, St John’s wort or serotonin syndrome.
How this applies: RxNorm IN 5691/PIN 150816 hydrochloride; pamoate capsule is not assumed the same tested formulation. Desipramine metabolite evidence is distinguished from directly prescribed imipramine.
No universal supplement interval, event rate or preparation equivalence established. Original label distinguishes warnings from measured pair-specific results.
Source 2: official botanical guidance
nccih.nih.gov · Source check Sep 10, 2026
Population: Users of Hypericum perforatum.
Certain antidepressant combinations may cause serious serotonin-related side effects; herb can reduce the effects of some medicines.
How this applies: Supports product-specific serotonergic caution, without generic PK extrapolation.
Does not quantify imipramine-specific risk or establish reduced absorption for every antidepressant.
Source 3: current oral product label
medicines.org.uk · Source check Sep 10, 2026
Population: Patients prescribed oral imipramine hydrochloride solution.
Warns about serotonin syndrome with other serotonergic agents and anticholinergic combinations.
How this applies: Ingredient pharmacodynamic warning context; formulation-specific dose instructions are not transferred.
Does not specifically name the requested supplements or establish tablet/solution pharmacokinetic equivalence.
Source 4: original human study
pubmed.ncbi.nlm.nih.gov · Source check Sep 10, 2026
Population: 324 outpatients with mild to moderate depression.
Both groups improved similarly; fewer adverse events with the tested herb extract.
How this applies: Only the named drug, preparation, route and measured endpoints apply.
Comparator trial, not concurrent administration. Relative tolerability cannot establish combination safety or reduced drug exposure.
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: f6e25d567dd4fe46
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.