The short answer
Review St John’s wort with the prescriber while taking ziprasidone. A specific supplement requirement or protective spacing interval has not been established.
What this answer covers
Oral Hypericum perforatum; ziprasidone oral and intramuscular routes distinguished.
- Supplement or preparation
- Hypericum perforatum
- Medication ingredient
- ziprasidone
The metabolism concern has limits
Ziprasidone is cleared through several pathways. Its label reports reduced exposure with carbamazepine, but that is not a St John’s wort study.
A clinical study did not show serious harm
The carbamazepine study found modest exposure reduction without serious adverse events or clinically important ECG changes. The authors considered the change clinically insignificant; this does not prove herb safety.
Herbal extracts are not interchangeable
St John’s wort probe results differ by extract and hyperforin content. Neither those studies nor general guidance supplies a ziprasidone-specific spacing rule.
Keep food and supplement instructions separate
Oral ziprasidone capsules must be taken with food. That instruction does not create a requirement to take St John’s wort and does not apply to injection absorption.
Evidence and practical considerations
Side effects & toxicity
Conditional review is reasonable; no automatic supplement need, dose change or validated interval.
- Exact scope
- Oral Hypericum perforatum; ziprasidone oral and intramuscular routes distinguished. with Exact ziprasidone hydrochloride oral capsules or mesylate intramuscular injection, distinguished by route. Exact RxNorm IN115698; hydrochloride oral capsule and mesylate intramuscular formulation distinct. Oral food and antacid findings do not apply to injection absorption.
- Medication form and route
- oral; intramuscular
- Timing or duration
- Source-specific single-dose, repeated-dose and observational exposures distinguished.
What remains uncertain
- No exact herb co-use trial. Oral CYP-inducer study does not establish injected-drug absorption or a clinically important herb effect.
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 ziprasidone.
Somnolence, QT and electrolyte precautions; low potassium or magnesium requires assessment/correction before proceeding; oral capsules taken with food.
How this applies: Exact RxNorm IN115698; hydrochloride oral capsule and mesylate intramuscular formulation distinct. Oral food and antacid findings do not apply to injection absorption.
No supplement-specific event rate, universal timing rule or untested route/preparation equivalence.
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: Preparation-specific evidence; exact ziprasidone co-use is not inferred from another medicine or route.
General herb-drug interaction guidance, not a measured ziprasidone interaction.
Source 3: original human study
pubmed.ncbi.nlm.nih.gov · Source check Sep 10, 2026
Population: Twenty-five randomized healthy adults; nineteen completed.
Ziprasidone exposure fell modestly; no serious adverse event or clinically significant ECG change. Authors considered the exposure change clinically insignificant.
How this applies: Only the named drug, preparation, route and measured endpoints apply.
Carbamazepine is not St John’s wort; no herb-specific effect, benefit or timing rule.
Source 4: original human study
pubmed.ncbi.nlm.nih.gov · Source check Sep 10, 2026
Population: Twelve healthy volunteers in an open-label fixed-order crossover.
Alprazolam exposure fell about one-half and clearance increased; elimination half-life shortened.
How this applies: Preparation-specific original evidence; no untested antidepressant or route transfer.
Single extract and short exposure, healthy volunteers; no anxiety-treatment failure endpoint. Does not imply reduced gut absorption or transfer to predominantly conjugated benzodiazepines.
Source 5: original human study
pubmed.ncbi.nlm.nih.gov · Source check Sep 10, 2026
Population: Healthy participants in randomized placebo-controlled studies.
Changes in probe exposures were small and judged clinically irrelevant; hyperforin levels were below quantification.
How this applies: Preparation-specific original evidence; no untested antidepressant or route transfer.
Preparation-specific result, not permission to assume all retail products are low-hyperforin or all doses safe.
Research assessment: · Open full citations ↗
Review and change history
- Publication status
- Published research summary
- Clinical review
- Not yet recorded
| Date | Update |
|---|---|
| Research summary published | |
| Article prepared | |
| Current exact available claims adjudicated using original captures and explicit identity and comparator limits. |
Article revision: bc051cc5726f551e
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.