Major interaction on record — check this product against your medications before combining. Based on 1 of 2 ingredients. Check your meds →
Dietary supplement

St. John's Wort Ingredients & Drug Interactions

by Vitanica

St. John's Wort label
See full label image
Capsule Category: Botanical
Most serious interaction: Major
Clinical methodology reviewed by · Updated Sep 9, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking St. John's Wort against your medications. The heart of this page is the interaction checker and the full interaction report — how this product’s ingredients may interact with prescription and over-the-counter medicines you may be taking.

Around that, we add a pharmacist’s high-level view of the product as a whole — what’s inside, the evidence for its stated use, how transparent the label is, and what safety data exists — so you can see the full picture in one place. It’s educational information from our licensed clinical databases and the clinical staff at HelloPharmacist — not medical advice — and we don’t sell or endorse products. Our editorial policy

The interaction bottom line Most serious interaction: Major

St. John's Wort is a dietary supplement by Vitanica with 2 active ingredients. Its ingredients are commonly taken for mild to moderate depression, anxiety and stress, sleep problems.Based on those ingredients, 1,143 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are St. John's wort flower extract. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against St. John's Wort by Vitanica

Ask about any prescription or over-the-counter medication and we check it for interactions with St. John's Wort by Vitanica — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of St. John's Wort by Vitanica

Our pharmacy team’s full take, with four database checks built into the cards below — a summary of what is known, not a grade of the product itself.

From our pharmacy team — supplement deep dive

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Jul 11, 2026

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 2 of its 2 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

St. John's Wort by Vitanica contains 2 active ingredients: St.

John's wort flower extract and St. John's wort herb.

Both come from the same plant and work the same way in your body. The product also includes vegetarian capsule material and L-leucine as inactive ingredients.

Does it work?

Strong evidence
Evidence for Intended Use · database check
By FDA rules, dietary supplements can’t claim to treat, cure, or prevent disease — so labels speak in careful marketing language. We discern each product’s intended use from its name, label claims, and label statements, then grade the clinical evidence for that use. How these ratings are computed
Strong

Clinical evidence supports at least one of this product's ingredients for its stated purpose.

Why this rating?
  • The label markets this product for: mood and emotional wellness support.
  • We looked for evidence on: Anxiety, Depression, Menopausal symptoms, Seasonal affective disorder (SAD), Social anxiety disorder, stress — and 1 related terms.
  • The strongest evidence on file: St. John's Wort is rated "Likely Effective" for Depression (Natural Medicines).
  • Also on file: St. John's Wort is rated "Possibly Effective" for Menopausal symptoms.
  • Also on file: St. John's Wort is rated "Possibly Ineffective" for Social anxiety disorder.

St. John's Wort is likely effective for depression—it's one of the better-studied uses for this herb.

It may help with somatic symptom disorder and menopausal symptoms, though the evidence is less solid. On the flip side, the data doesn't support it for HIV/AIDS or irritable bowel syndrome (IBS); in fact, it appears ineffective for those.

The evidence, ingredient by ingredient St. John's Wort

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

Adverse-effect, pregnancy, and general safety data are on file for most of these ingredients.

Why this rating?
  • We hold adverse-effect (side-effect) data for 1 of the 1 matched ingredient.
  • Pregnancy & breastfeeding safety ratings cover 1 of 1.
  • General safety write-ups exist for 1 of 1.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

St. John's Wort is generally well tolerated in the short term, but sun sensitivity is a real concern.

Common side effects include diarrhea, dizziness, dry mouth, mild stomach upset, fatigue, headache, insomnia, restlessness, and drowsiness. Rare but serious side effects reported include suicidal thoughts and psychosis.

It can also trigger or worsen mania in people with bipolar disorder, even if you didn't know you had it. The safety data during pregnancy is not strong enough to recommend it, so it's best avoided.

It passes into breast milk and can cause side effects in infants, so don't use it while breastfeeding.

Side effects, ingredient by ingredient St. John's Wort

Meds to double-check

Major interaction found
Known Interaction Concern · database check
Major identified

At least one ingredient has a documented Major-severity interaction. Check your medications for a personalized result.

Why this rating?
  • 1 of the 1 matched ingredient can interact with medications — St. John's Wort.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; immunosuppressants / transplant drugs; heart-rhythm medications.
  • For scale: 1,144 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Before you start St. John's Wort, double-check with your pharmacist if you take any of these: heart medications like digoxin, seizure drugs (phenytoin, phenobarbital, mephenytoin), cancer treatments (irinotecan, docetaxel), HIV protease inhibitors, or transplant rejection medications like tacrolimus.

All of these interactions are Major severity.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with clinical evidence supporting its stated purpose. Major medication interactions have been identified, and safety information is well characterized.

St. John's Wort works for depression and is worth considering if you're looking for a herbal option—but only if you're not on other medications.

If you take heart drugs, seizure meds, cancer treatments, HIV medications, or transplant drugs, you need to talk with your pharmacist first. Pregnant or breastfeeding?

Skip it.

Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI

Assessment coverage: 2 of 2 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Jun 25, 2014.

This Scorecard evaluates available label information, ingredient evidence, and known medication-safety considerations. It does not independently verify product identity, purity, potency, contamination, or manufacturing quality. How these ratings are computed

At a glance

General information

Key facts about St. John's Wort, straight from the product label.

Brand Vitanica
Barcode (UPC) 708118010804
Net contents 90 Capsule(s)
Market status On market
Date entered into DSLD Jun 25, 2014
DSLD ID 33884
Product type Botanical
Supplement form Capsule
Dietary claims / uses All Other
Intended target group(s) Vegetarian, Adult (18 - 50 Years), Gluten Free, Dairy Free, Sugar Free
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for St. John's Wort by Vitanica, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
1 Capsule(s)
Maximum serving Sizes:
3 Capsule(s)
UPC/BARCODE
708118010804
IngredientAmount% DV
St. John's wort flower extract300 mg--
St. John's wort herb100 mg--

Other ingredients: vegetarian capsule, L-Leucine

Tap any ingredient to jump to its full detail below.

Label statements
These statements are the manufacturer’s wording, reproduced from the product label — the label is saying it, not HelloPharmacist. We don’t verify or endorse them.
FDA Statement of Identity

Dietary Supplement

Formula

HYPERICUM EXTRACT PLUS

Formulation

St. John's Wort(TM) is suitable for vegetarians.

This product contains no: preservatives, binders, artificial colorings or flavorings, sugars, starch, lactose, salt, corn, wheat, gluten, soy or milk derivatives.

Suggested/Recommended/Usage/Directions

Suggested Use: One (1) to three (3) capsules daily.

Precautions

If taking prescription drugs, consult with your health care practitioner.

Use caution with UV exposure.

Avoid if pregnant, nursing or have bi-polar disorder.

Tamper resistant: please do not use if safety seal is broken or missing.

Keep in a cool, dry place out of reach of children.

Storage

Keep in a cool, dry place out of reach of children.

General Statements

b

Is this label outdated? Report a formula or label change and our pharmacy team will review it.

See for yourself

St. John's Wort by Vitanica label

The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.

St. John's Wort label

Label images are published by the NIH Dietary Supplement Label Database for the version of this product on file. Always read your actual product label.

View the full label (PDF)
What’s inside

The Ingredients in St. John's Wort by Vitanica

These are the 2 active ingredients this product is made of. Select any to open its full monograph.

Serving size1 Capsule(s) Dosage formCapsule Amounts shown are per serving.

Most supplement products combine several ingredients, and a medication can interact with the product through any one of them. Each ingredient below shows whether it has known drug interactions.

St. John's wort flower extract

Interacts with
1,143 drugs
300 mg per serving Form: Hypericins

St. John's wort is a well-studied herb most often used for mild to moderate depression, and some research suggests it may help with this. However, it...

St. John's wort flower extract monograph & interactions

St. John's wort herb

Interacts with
1,143 drugs
100 mg per serving

St. John's wort is a well-studied herb most often used for mild to moderate depression, and some research suggests it may help with this. However, it...

St. John's wort herb monograph & interactions

Other (inactive) ingredients: Vegetarian capsule, L-Leucine. These complete the product’s ingredient list but are not active constituents.

Interaction report

St. John's Wort by Vitanica Drug Interactions

Want to check YOUR meds against St. John's Wort?

Ask about interactions with your drugs in plain English — “Can I take it with lisinopril?” — and we find you the answer in seconds, ingredient by ingredient.

 Go to the checker
1,143Drugs
755 Major 388 Moderate

Ingredients driving the most interactions

St. John's wort flower extract 1,143

Individual Drug Interactions

The ingredients in St. John's Wort interact with 1,143 drugs. Click any drug to see the details.

1 of the 2 ingredients in St. John's Wort interact with drugs. Each result below shows which ingredient is responsible. St. John's wort flower extract

Each ingredient & the kinds of drugs it affects

For each ingredient in St. John's Wort with known interactions, here are the types of medications it can affect. Open any type for the detail — or search your exact drug in the checker above.

St. John's wort flower extract47 drug types · 1,143 drugs

Alprazolam (Xanax)

St. John's wort increases the clearance of alprazolam and decreases its effects.
Alprazolam, which is used as a probe for cytochrome P450 3A4 (CYP3A4) activity, has a two-fold increase in clearance when given with St. John's wort. St. John's wort reduces the half-life of alprazolam from 12.4 hours to 6 hours.

Likelihood Likely Evidence B
Contraceptive Drugs

St. John's wort increases the clearance of contraceptive drugs and reduces their clinical effects.
Females taking St. John's wort and oral contraceptives concurrently should use an additional or alternative form of birth control. St. John's wort can decrease norethindrone and ethinyl estradiol levels by 13% to 15%, resulting in breakthrough bleeding, irregular menstrual bleeding, or unplanned pregnancy. Bleeding irregularities usually occur within a week of starting St. John's wort and regular cycles usually return when St. John's wort is discontinued. Unplanned pregnancy has occurred with concurrent use of oral contraceptives and St. John's wort extract. St. John's wort is thought to induce the cytochrome P450 1A2 (CYP1A2), 2C9 (CYP2C9), and 3A4 (CYP3A4) enzymes, which are responsible for metabolism of progestins and estrogens in contraceptives.

Likelihood Probable Evidence B
Cyclosporine (Neoral, Sandimmune)

St. John's wort reduces the levels and clinical effects of cyclosporine.
Concomitant use can decrease plasma cyclosporine levels by 30% to 70%. Using St. John's wort with cyclosporine in patients with heart, kidney, or liver transplants can cause subtherapeutic cyclosporine levels and acute transplant rejection. This interaction has occurred with a St. John's wort extract standardized to 0.3% hypericin and dosed at 300-600 mg per day. Withdrawal of St. John's wort can result in a 64% increase in cyclosporine levels. St. John's wort induces cytochrome P450 3A4 (CYP3A4) and the multi-drug transporter, P-glycoprotein/MDR-1, which increases cyclosporine clearance.

Likelihood Probable Evidence B
Cytochrome P450 3A4 (Cyp3A4) Substrates

St. John's wort increases the metabolism and reduces the levels of CYP3A4 substrates.
St. John's wort induces CYP3A4 enzymes and increases metabolism of CYP3A4 substrates. Clinically significant interactions have been reported with St. John's wort products containing hyperforin 1 mg or more.

Likelihood Probable Evidence B
Digoxin (Lanoxin)

St. John's wort reduces the levels and clinical effects of digoxin.
St. John's wort can reduce the bioavailability, serum levels, and therapeutic effects of digoxin. Taking an extract of St. John's wort 900 mg, containing hyperforin 7.5 mg or more, daily for 10-14 days, can reduce serum digoxin levels by 25% in healthy people. St. John's wort is thought to affect the multidrug transporter, P-glycoprotein, which mediates the absorption and elimination of digoxin and other drugs. St. John's wort products providing less than 7.5 mg of hyperforin daily do not appear to affect digoxin levels.

Likelihood Likely Evidence B
Docetaxel (Taxotere)

St. John's wort reduces the levels and clinical effects of docetaxel.
Clinical research shows that taking a specific St. John's wort product (Hyperiplant, VSM) 300 mg three times daily for 14 days increases docetaxel clearance by about 14%, resulting in decreased plasma concentrations of docetaxel in cancer patients. This is most likely due to induction of cytochrome P450 3A4 (CYP3A4) by St. John's wort.

Likelihood Probable Evidence B
Imatinib (Gleevec)

St. John's wort reduces the levels and clinical effects of imatinib.
Taking St. John's wort 900 mg daily for 2 weeks reduces the bioavailability and half-life of a single dose of imatinib and decreases its serum levels by 30% in healthy volunteers. This is most likely due to induction of cytochrome P450 3A4 (CYP3A4) by St. John's wort, which increases clearance of imatinib.

Likelihood Likely Evidence A
Irinotecan (Camptosar)

St. John's wort reduces the levels and clinical effects of irinotecan.
St. John's wort 900 mg daily for 18 days decreases serum levels of irinotecan by at least 50%. Clearance of the active metabolite of irinotecan, SN-38, is also increased, resulting in a 42% decrease in the area under the concentration-time curve. This is thought to be due to induction of cytochrome P450 3A4 (CYP3A4) by St. John's wort.

Likelihood Likely Evidence A
Mephenytoin (Mesantoin)

St. John's wort reduces the levels and clinical effects of mephenytoin.
Preliminary clinical research in healthy males shows that taking St. John's wort for 14 days induces cytochrome P450 2C19 (CYP2C19) and significantly increases metabolism of mephenytoin (Mesantoin). In people with wild-type 2C19, metabolism was almost 4-fold greater in subjects who received St. John's wort compared to placebo. In contrast, patients with 2C19*2/*2 and *2/*3 genotypes did not demonstrate a similar increase in metabolism.

Likelihood Likely Evidence B
Non-Nucleoside Reverse Transcriptase Inhibitors (Nnrtis)

St. John's wort decreases the levels and clinical effects of NNRTIs.
St. John's wort increases the oral clearance of nevirapine (Viramune) by 35%. Subtherapeutic concentrations are associated with therapeutic failure, development of viral resistance, and development of drug class resistance. St. John's wort induces intestinal and hepatic cytochrome P450 3A4 (CYP3A4) and intestinal P-glycoprotein/MDR-1, a drug transporter.

Likelihood Likely Evidence B
Omeprazole (Prilosec)

St. John's wort decreases the levels and clinical effects of omeprazole.
Taking St. John's wort, 300 mg orally three times daily for 14 days, reduces serum concentrations of omeprazole by inducing its metabolism via cytochrome P450 (CYP) 2C19 and 3A4. The reduction of omeprazole serum levels is dependent on CYP2C19 genotype, with reductions up to 50% in extensive metabolizers and 38% in poor metabolizers.

Likelihood Likely Evidence B
Oxycodone (Oxycontin)

St. John's wort decreases the levels and clinical effects of oxycodone.
St. John's wort can increase oxycodone metabolism by inducing cytochrome P450 3A4 (CYP3A4), reducing plasma levels and analgesic activity.

Likelihood Probable Evidence B
P-Glycoprotein Substrates

St. John's wort decreases the levels and clinical effects of P-glycoprotein substrates.
St. John's wort induces P-glycoprotein. P-glycoprotein is a carrier mechanism responsible for transporting drugs and other substances across cell membranes. When P-glycoprotein is induced in the gastrointestinal (GI) tract, it can prevent the absorption of some medications. In addition, induction of p-glycoprotein can decrease entry of drugs into the central nervous system (CNS) and decrease access to other sites of action.

Likelihood Probable Evidence B
Phenobarbital (Luminal)

St. John's wort decreases the levels and clinical effects of phenobarbital.
St. John's wort may increase the metabolism of phenobarbital. Plasma concentrations of phenobarbital should be monitored carefully. The dose of phenobarbital may need to be increased when St. John's wort is started and decreased when it is stopped.

Likelihood Likely Evidence B
Phenprocoumon (Marcoumar, Others)

St. John's wort decreases the levels and clinical effects of phenprocoumon.
St. John's wort appears to increase the metabolism of phenprocoumon (an anticoagulant that is not available in the US) by increasing the activity of the cytochrome P450 2C9 (CYP2C9) enzyme. This may result in decreases in the anticoagulant effect and international normalized ratio (INR).

Likelihood Likely Evidence B
Phenytoin (Dilantin)

St. John's wort decreases the levels and clinical effects of phenytoin.
St. John's wort may increase the metabolism of phenytoin. Plasma concentrations of phenytoin should be monitored closely. The dose of phenytoin may need to be increased when St. John's wort is started and decreased when it is stopped.

Likelihood Likely Evidence B
Protease Inhibitors (Pis)

St. John's wort reduces the levels and clinical effects of PIs.
In healthy volunteers, St. John's wort can reduce the plasma concentrations of indinavir (Crixivan) by inducing cytochrome P450 3A4 (CYP3A4). This might result in treatment failure and viral resistance. St. John's wort also induces P-glycoprotein, which can result in decreased intracellular protease inhibitor concentrations and increased elimination.

Likelihood Likely Evidence B
Rivaroxaban (Xarelto)

St. John's wort decreases the levels and clinical effects of rivaroxaban.
A small pharmacokinetic study in healthy volunteers shows that taking a single dose of rivaroxaban 20 mg after using a specific St. John's wort extract (Jarsin, Vifor SA) 450 mg orally twice daily for 14 days reduces the bioavailability of rivaroxaban by 24% and reduces rivaroxaban's therapeutic inhibition of factor Xa by 20%.

Likelihood Probable Evidence B
Tacrolimus (Prograf)

St. John's wort decreases the levels and clinical effects of tacrolimus.
Taking a St. John's wort extract (Jarsin) 600 mg daily significantly decreases tacrolimus serum levels. Dose increases of 60% may be required to maintain therapeutic tacrolimus levels in patients taking St. John's wort. St. John's wort is thought to lower tacrolimus levels by inducing cytochrome P450 3A4 (CYP3A4) enzymes. A small clinical study in healthy adults also shows that taking St. John's wort 300 mg three times daily for 10 days decreases the total systemic exposure to tacrolimus by 27% and 33% after taking a single 5 mg dose of immediate-release or prolonged-release tacrolimus, respectively.

Likelihood Likely Evidence B
Warfarin (Coumadin)

St. John's wort decreases the levels and clinical effects of warfarin.
Taking St. John's wort significantly increases clearance of warfarin, including both its R- and S-isomers. This is likely due to induction of cytochrome P450 (CYP) 1A2 and CYP3A4. St. John's wort can also significantly decrease International Normalized Ratio (INR) in people taking warfarin. In addition, taking warfarin at the same time as St. John's wort might reduce warfarin bioavailability. When a dried extract is mixed with warfarin in an aqueous medium, up to 30% of warfarin is bound to particles, reducing its absorption.

Likelihood Likely Evidence B
Aminolevulinic Acid

St. John's wort might have additive phototoxic effects with aminolevulinic acid.
Concomitant use with St. John's wort extract may cause synergistic phototoxicity. Delta-aminolevulinic acid can cause a burning erythematous rash and severe swelling of the face, neck, and hands when taken with St. John's wort.

Likelihood Possible Evidence D
Bupropion (Wellbutrin)

St. John's wort might reduce the levels and effects of bupropion.
Clinical research shows that taking St. John's wort 325 mg three times daily for 14 days along with bupropion reduces the area under the concentration-time curve by approximately 14% and increases the clearance of bupropion by approximately 20%. This effect is attributed to the induction of cytochrome P450 2B6 (CYP2B6) by St. John's wort.

Likelihood Probable Evidence B
Clopidogrel (Plavix)

St. John's wort might increase the levels and effects of clopidogrel.
Taking St. John's wort with clopidogrel seems to increase the activity of clopidogrel. In clopidogrel non-responders, taking St. John's wort seems to induce metabolism of clopidogrel to its active metabolite by cytochrome P450 enzymes 3A4 and 2C19. This leads to increased antiplatelet activity. Theoretically, this might lead to an increased risk of bleeding in clopidogrel responders.

Likelihood Possible Evidence B
Clozapine (Clozaril)

St. John's wort might decrease the levels and clinical effects of clozapine.
A case report describes a female with schizophrenia controlled on clozapine who had a return of symptoms when she started taking St. John's wort. The plasma concentration of clozapine was reduced, likely because its clearance was increased due to induction of the cytochrome P450 enzymes 3A4, 1A2, 2C9, and 2C19 by St. John's wort.

Likelihood Possible Evidence D
Cytochrome P450 1A2 (Cyp1A2) Substrates

St. John's wort may increase the metabolism and reduce the levels of CYP1A2 substrates.
Clinical and in vitro research shows that St. John's wort induces CYP1A2, but to a lesser extent than CYP3A4.

Likelihood Possible Evidence B
St. John's wort flower extract full monograph & all 47 interactions
The maker

Brand information

Manufacturer and brand details for St. John's Wort, from the product label.

Vitanica

See all Vitanica products
Name
VITANICA(R)
Street Address
10347 SW Spokane Ct.
City
Tualatin
State
OR
ZipCode
97062
Pharmacist Counseling Corner

St. John's Wort by Vitanica: Common Questions

Does St. John's Wort by Vitanica interact with any medications?
Yes. Based on its ingredients, St. John's Wort has a known interaction with 1,143 medications, including 755 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
St. John's Wort contains 2 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Does St. John's Wort really work for depression?
Yes—it's likely effective for depression based on the evidence we have. That said, it interacts with a lot of medications, so you'll want to check with your pharmacist before starting, especially if you're on any prescription drugs.
What are the most common side effects?
You might experience diarrhea, dizziness, dry mouth, mild stomach upset, fatigue, headache, insomnia, restlessness, or drowsiness. Most people tolerate it well short-term. If you're out in the sun a lot, be aware that St. John's Wort can increase your skin sensitivity to sunlight.
Can I take this if I'm pregnant or breastfeeding?
No. There isn't enough reliable safety data to recommend it during pregnancy, so it's best avoided. It also passes into breast milk and can cause side effects in infants, so don't use it while breastfeeding.
What's the difference between the flower extract and the herb in this product?
Both come from the same St. John's Wort plant and work the same way in your body. They're just different forms of the same plant material.
Can St. John's Wort cause suicidal thoughts or psychosis?
It's rare, but there have been case reports of suicidal ideation and psychosis after taking St. John's Wort. It can also trigger or worsen mania or a first episode of psychosis in some people. If you notice any changes in your mood or thoughts, stop and call your doctor right away.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

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Label information is sourced from the NIH Dietary Supplement Label Database and reflects the product version on file; always read your actual product label. This page is for education only and is not a substitute for professional medical advice. Confirm with your pharmacist or doctor before combining supplements and medications.

St. John's Wort label
Go deeper

The Full Monographs Behind St. John's Wort’s Ingredients

Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.

Herb & supplement monograph

St. John's Wort

Interacts with 1,143 drugs

St. John's wort is a well-studied herb most often used for mild to moderate depression, and some research suggests it may help with this. However, it has many serious interactions with presc...

Read the full St. John's Wort monograph →
Sources

Sources & How We Checked

St. John's Wort's label data comes from the NIH Dietary Supplement Label Database; the ingredient interaction data is from the Natural Medicines database, reviewed by our pharmacists.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

The 152 references behind this product’s interaction data

Every citation that drives the interaction findings for this product’s ingredients, from the evidence-graded Natural Medicines (TRC Healthcare) database. Open an ingredient to browse its citations — links open the study on PubMed or the publisher’s site.

St. John's Wort 152 references
  1. Miller LG. Herbal Medicinals: Selected clinical considerations focusing on known or potential drug-herb interactions. Arch Intern Med 1998;158:2200-11.
  2. Gulick RM, McAuliffe V, Holden-Wiltse J, et al. Phase I studies of hypericin, the active compound in St. John's Wort, as an antiretroviral agent in HIV-infected adults. AIDS Clinical Trials Group Protocols 150 and 258. Ann Intern Med 1999;130:510-4. PubMed
  3. O'Breasail AM, Argouarch S. Hypomania and St John's wort. Can J Psychiatry 1998;43:746-7.
  4. Johne A, Brockmoller J, Bauer S, et al. Pharmacokinetic interaction of digoxin with an herbal extract from St John's wort (Hypericum perforatum). Clin Pharmacol Ther 1999;66:338-45.
  5. Gordon JB. SSRIs and St. John's Wort: possible toxicity? Am Fam Physician 1998;57:950, 953.
  6. Golsch S, Vocks E, Rakoski J, et al. [Reversible increase in photosensitivity to UV-B caused by St. John's wort extract]. Hautarzt 1997;48:249-52.
  7. Bove GM. Acute neuropathy after exposure to sun in a patient treated with St. John's Wort. Lancet 1998;352:1121-2. PubMed
  8. Brockmoller J, Reum T, Bauer S, et al. Hypericin and pseudohypericin: pharmacokinetics and effects on photosensitivity in humans. Pharmacopsychiatry 1997;30:94-101. PubMed
  9. Upton R, ed. St. John's wort, Hypericum perforatum: Quality control, analytical and therapeutic monograph. Santa Cruz, CA: American Herbal Pharmacopoeia 1997;1-32.
  10. Muller WE, Singer A, Wonnemann M, et al. Hyperforin represents the neurotransmitter reuptake inhibiting constituent of hypericum extract. Pharmacopsychiatry 1998;31:16-21.
  11. Abul-Ezz SR, Barone GW, Gurley BJ, et al. Effect of herbal supplements on cyclosporine blood levels and associated acute rejection. Am Soc of Nephrol Ann Mtg, Toronto, CAN 2000;Oct. 11-16:abstract A3754.
  12. Piscitelli SC, Burstein AH, Chaitt D, et al. Indinavir concentrations and St John's wort. Lancet 2000;355:547-8. PubMed
  13. Yue QY, Bergquist C, Gerden B. Safety of St. John's wort (Hypericum perforatum). Lancet 2000;355:576-7. PubMed
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See these in context on the St. John's Wort monograph →

Parts of this content are provided by the Therapeutic Research Center, LLC.

DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

© 2021 Therapeutic Research Center, LLC

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