Major interaction on record — check this product against your medications before combining. Check your meds →
Dietary supplement

St. John's Wort 300 mg Ingredients & Drug Interactions

by up&up

St. John's Wort 300 mg label
See full label image
Other (e.g. Tea Bag) 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 300 mg 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 300 mg is a dietary supplement by up&up with 1 active ingredient. 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 (Hypericum perforatum) (aerial parts) standardized extract. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against St. John's Wort 300 mg by up&up

Ask about any prescription or over-the-counter medication and we check it for interactions with St. John's Wort 300 mg by up&up — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
Prefer a human? Send your question to our licensed pharmacists — free, answered by email within 24 hours.

HelloPharmacist Scorecard of St. John's Wort 300 mg by up&up

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 1 of its 1 active ingredient.
  • No proprietary blends here — you can verify the dose of every single component.

St. John's Wort 300 mg by up&up contains one active ingredient: a standardized extract of St.

John's wort aerial parts (the above-ground flowering portions of the plant). The product also includes inactive ingredients—dicalcium phosphate, maltodextrin, microcrystalline cellulose, croscarmellose sodium, tricalcium phosphate, stearic acid, magnesium stearate, hypromellose, hydroxypropyl cellulose, and polyethylene glycol—which serve as binders, fillers, and capsule material.

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: helps support a positive mood.
  • We looked for evidence on: Anxiety, Depression, Seasonal affective disorder (SAD), Social anxiety disorder, mood balance, emotional wellness.
  • 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 Ineffective" for Social anxiety disorder.
  • Also on file: St. John's Wort is rated "Insufficient Reliable Evidence To Rate" for Anxiety, Seasonal affective disorder (SAD).

St. John's wort is likely effective for depression—the main condition it's used for.

For somatic symptom disorder (persistent physical symptoms tied to stress or anxiety) and menopausal symptoms, the evidence suggests it may help, though the data is less solid. For HIV/AIDS and irritable bowel syndrome (IBS), it appears ineffective according to the evidence we hold.

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 it comes with real cautions.

The most common side effects are diarrhea, dizziness, dry mouth, mild stomach upset, fatigue, headache, insomnia, restlessness, and sedation. It can also cause sun sensitivity (photodermatitis)—your skin may react badly to sunlight, especially at higher doses or with prolonged use.

Rare but serious effects include suicidal thoughts and psychosis, and it can trigger mania or first-episode psychosis in some people, particularly those with undiagnosed bipolar disorder. Don't use this supplement during pregnancy—there isn't enough safety data.

Avoid it while breastfeeding too, since it may pass into breast milk and affect your infant.

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 taking this product, check if you're on digoxin or other heart medications, seizure drugs (phenytoin, phenobarbital, mephenytoin), cancer drugs (irinotecan, docetaxel), HIV protease inhibitors, or tacrolimus. St.

John's wort speeds up how your liver breaks these down, which can make them much less effective or require dose changes. Use the medication checker on this page to verify your exact drugs.

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 300 mg works for depression, but it's a strong herb with major drug interactions—especially with heart meds, seizure drugs, cancer treatments, and HIV protease inhibitors.

If you take any prescription medications, check them against our database before starting. Talk to your pharmacist or doctor about whether this is right for you, and watch for mood changes or skin reactions to sun.

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

Assessment coverage: 1 of 1 active ingredient matched to our full ingredient reviews (monographs). Based on the product label dated May 24, 2013.

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 300 mg, straight from the product label.

Brand up&up
Barcode (UPC) 070030625221
Net contents 120 Caplet(s)
Market status On market
Date entered into DSLD May 24, 2013
DSLD ID 20197
Product type Botanical
Supplement form Other (e.g. Tea Bag)
Dietary claims / uses All Other, Structure/Function
Intended target group(s) 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 300 mg by up&up, 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 Caplet(s)
Maximum serving Sizes:
1 Caplet(s)
UPC/BARCODE
070030625221
IngredientAmount% DV
St. John's Wort (Hypericum perforatum) (aerial parts) standardized extract300 mg--

Other ingredients: Dicalcium Phosphate, Maltodextrin, Microcrystalline Cellulose, Croscarmellose Sodium, Tricalcium Phosphate, Stearic Acid, Magnesium Stearate, Hypromellose, Hydroxypropyl Cellulose, Polyethylene Glycol

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.
General Statements

ACTUAL SIZE

standardized extract

helps support a positive mood**

BALANCE** St. john's wort helps maintain a healthy emotional balance.**

Used as a supplement, st. john's wort helps support a positive mood.**

EXP10/15 3AN1408

ID482463

Seals/Symbols

up&up(TM)

BALANCE**

FDA Statement of Identity

DIETARY SUPPLEMENT

FDA Disclaimer Statement

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

Formulation

No yeast, wheat, gluten, milk or milk derivatives, lactose, sugar, preservatives, soy, artificial color, artificial flavor.

GLUTEN FREE

General

094 02 2194 : 2F976 UW F1

Brand IP Statement(s)

(C) 2012 Target Brands, Inc.

Formula

This formula is standardized to contain 0.3% hypericin.

Suggested/Recommended/Usage/Directions

Suggested Use: As a dietary supplement for adults, take one caplet three times daily.

Precautions

If you are pregnant or nursing a baby, ask a doctor before using this product.

CAUTION: If you take a prescription medication or plan to have surgery, consult a physician before taking this product.

Limit exposure to natural or artificial sunlight as St. John's Wort may cause skin to be extra sensitive to sunlight. Discontinue use if any adverse or allergic reaction occurs.

Keep out of reach of children.

Storage

Store at room temperature (59(0)-86(0)F).

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

See for yourself

St. John's Wort 300 mg by up&up label

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

St. John's Wort 300 mg 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 300 mg by up&up

This is the 1 active ingredient this product is made of. Select it to open its full monograph.

Serving size1 Caplet(s) Dosage formOther (e.g. Tea Bag) Amounts shown are per serving.

St. John's Wort (Hypericum perforatum) (aerial parts) standardized extract

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

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 (Hypericum perforatum) (aerial parts) standardized extract monograph & interactions

Other (inactive) ingredients: Dicalcium Phosphate, Maltodextrin, Microcrystalline Cellulose, Croscarmellose Sodium, Tricalcium Phosphate, Stearic Acid, Magnesium Stearate, Hypromellose, Hydroxypropyl Cellulose, Polyethylene Glycol. These complete the product’s ingredient list but are not active constituents.

Interaction report

St. John's Wort 300 mg by up&up Drug Interactions

Want to check YOUR meds against St. John's Wort 300 mg?

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 (Hypericum perforatum) (aerial parts) standardized extract 1,143

Individual Drug Interactions

The ingredients in St. John's Wort 300 mg interact with 1,143 drugs. Click any drug to see the details.

1 of the 1 ingredient in St. John's Wort 300 mg interact with drugs. Each result below shows which ingredient is responsible. St. John's Wort (Hypericum perforatum) (aerial parts) standardized extract

Each ingredient & the kinds of drugs it affects

For each ingredient in St. John's Wort 300 mg 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 (Hypericum perforatum) (aerial parts) standardized 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 (Hypericum perforatum) (aerial parts) standardized extract full monograph & all 47 interactions
The maker

Brand information

Manufacturer and brand details for St. John's Wort 300 mg, from the product label.

up&up

See all up&up products
Name
Target Corporation
City
Minneapolis
State
MN
ZipCode
55403
Pharmacist Counseling Corner

St. John's Wort 300 mg by up&up: Common Questions

Does St. John's Wort 300 mg by up&up interact with any medications?
Yes. Based on its ingredients, St. John's Wort 300 mg 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 300 mg contains a single active ingredient, and that one ingredient can interact with many different medications on its own. We check it against each medication and show the mechanism 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.
What is St. John's wort actually used for?
It's mainly used for depression, where it's well supported by evidence. It may also help with somatic symptom disorder and menopausal symptoms, though the evidence is weaker for those.
Can I take this while I'm pregnant?
No. There isn't enough reliable safety data, so it's best to avoid it during pregnancy. Talk to your doctor about other options if depression or other symptoms need treatment.
Will St. John's wort make me sensitive to the sun?
Yes, it can cause photodermatitis—your skin may react badly to sunlight. This is more likely at higher doses or with long-term use. If you take this, be extra careful with sun exposure and wear sunscreen.
What are the most common side effects I might notice?
Diarrhea, dizziness, dry mouth, mild stomach upset, fatigue, headache, insomnia, and restlessness are the most common. Most people tolerate it okay in the short term, but watch for mood changes or unusual thoughts.
Can I breastfeed while taking this?
No. St. John's wort passes into breast milk and may cause side effects in your baby, so avoid it while nursing.
Why does this supplement interact with so many drugs?
St. John's wort activates enzymes in your liver that break down many medications faster, making them less effective. That's why it's critical to check your exact prescriptions before starting it.

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

Not sure if St. John's Wort 300 mg is safe with your meds?

Our pharmacists answer your medication & supplement questions — free.

Ask a pharmacist

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 300 mg label
Go deeper

The Full Monographs Behind St. John's Wort 300 mg’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 300 mg'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
  14. Ruschitzka F, Meier PJ, Turina M, et al. Acute heart transplant rejection due to Saint John's wort. Lancet 2000;355:548-9. PubMed
  15. Roberts JE, Wang RH, Tan IP, et al. Hypericin (active ingredient in St. John's wort) photo-oxidation of lens proteins. Photochem Photobiol 1999;69:42S.
  16. Gurley BJ, Barone GW. Herb-drug interaction involving St. John's wort and cyclosporine. AAPS Ann Mtg & Expo Indianapolis, IN:2000;Oct 29- Nov 2: presentation #3443.
  17. Durr D, Stieger B, Kullak-Ublick GA, et al. St. John's Wort induces intestinal P-glycoprotein/MDR1 and intestinal and hepatic CYP3A4. Clin Pharmacol Ther 2000;68:598-604. PubMed
  18. Lee A, Minhas R, Ito S, et al. Safety of St. John's wort during breastfeeding. Clin Pharmacol Ther 2000;67:130, abstract PII-64.
  19. Schneck C. St. John's wort and hypomania. J Clin Psychiatry 1998;59:689. PubMed
  20. Nierenberg AA, Burt T, Matthews J, et al. Mania associated with St. John's wort. Biol Psychiatry 1999;46:1707-8. PubMed
  21. Nebel A, Schneider BJ, Baker RA, et al. Potential metabolic interaction between St. John's wort and theophylline. Ann Pharmacother 1999;33:502. PubMed
  22. Moses EL, Mallinger AG. St. John's wort: Three cases of possible mania induction. J Clin Psychopharmacol 2000;20:115-7. PubMed
  23. Beckman SE, Sommi RW, Switzer J. Consumer use of St. John's wort: A survey of effectiveness, safety, and tolerability. Pharmacotherapy 2000;20:568-74.
  24. Peirce A. The American Pharmaceutical Association Practical Guide to Natural Medicines. New York, NY: William Morrow and Co., 1999.
  25. Mai I, Kruger H, Budde K, et al. Hazardous pharmacokinetic interaction of Saint John's wort (Hypericum perforatum) with the immunosuppressant cyclosporin. Int J Clin Pharmacol Ther 2000;38:500-2. PubMed
  26. Schempp CM, Muller K, Winghofer B, et al. Single-dose and steady-state administration of Hypericum perfotatum extract (St. John's wort) does not influence skin sensitivity to UV radiation, visible light, and solar-stimulated radiation. Arch Dermatol 2001;
  27. Schempp CM, Ludtke R, Winghofer B, Simon JC. Effect of topical application of hypericum perforatum extract on skin sensitivity to solar simulated radiation. Photodermatol Photoimmunol Photomed 2000;16:125-8.
  28. Jacobson JM, Feinman L, Liebes L, et al. Pharmacokinetics, safety, and antiviral effects of hypericin, a derivative of St. John's Wort plant, in patients with chronic hepatitis C virus infection. Antimicrob Agents Chemother 2001;45:517-24. PubMed
  29. Moschella C, Jaber BL. Interaction between cyclosporine and Hypericum perforatum (St. John's wort) after organ transplantation. Amer J Kidney Dis 2001;38:1105-7. PubMed
  30. Karliova M, Treichel U, Malago M, et al. Interaction of Hypericum perforatum (SJW) with cyclosporin A metabolism in a patient after liver transplantation. J Hepatol 2000;33:853-5.
  31. Mandelbaum A, Pertzborn F, Martin-Facklam M, Wiesel M. Unexplained decrease of cyclosporin trough levels in a compliant renal transplant patient. Nephrol Dial Transplant 2000;15:1473-4. PubMed
  32. Assalian P. Sildenafil for SJW-induced sexual dysfunction. J Sex Marital Ther 2000;26:357-8.
  33. de Maat M, Hoetelmans R, Mathot R, et al. Drug interaction between St. John's wort and nevirapine. AIDS 2001;15:420-1. PubMed
  34. Schrader E. Equivalence of St. John's wort extract (Ze 117) and fluoxetine: a randomized, controlled study in mild-moderate depression. Int Clin Psychopharmacol 2000;15:61-8.
  35. Ernst E, Rand JI, Barnes J, Stevinson C. Adverse effects profile of the herbal antidepressant St. John's wort (Hypericum perforatum L.). Eur J Clin Pharmacol 1998;54:589-94. PubMed
  36. Shelton RC, Keller MB, Gelenberg A, et al. Effectiveness of St. John's wort in major depression: A randomized, placebo-controlled trial. JAMA 2001;285:1978-86. DOI
  37. Breidenbach T, Hoffmann MW, Becker T, et al. Drug interaction of St. John's wort with cyclosporin. Lancet 2000;355:1912.
  38. Brown TM. Acute St. John's wort toxicity. Am J Emerg Med 2000;18:231-2. PubMed
  39. Kleber E, Obry T, Hippeli S, et al. Biochemical activities of extracts from Hypericum perforatum L. 1st Communication: inhibition of dopamine-beta-hydroxylase. Arzneimittelforschung 1999;49:106-9.
  40. Barone GW, Gurley BJ, Ketel BL, et al. Drug interaction between St. John's wort and cyclosporin. Ann Pharmacother 2000;34:1013-6.
  41. Cheng TO. St. John's wort interaction with digoxin [letter]. Arch Intern Med 2000;160:2548. PubMed
  42. Lane-Brown MM. Photosensitivity associated with herbal preparations of St. John's wort (Hypericum perforatum). Med J Aust 2000;172:302.
  43. Mathijssen RHJ, Verweij J, De Bruijn P, et al. Modulation of irinotecan (CPT-11) metabolism by St. John's wort in cancer patients. American Association for Cancer Research Annual Meeting, San Francisco, April 2002. Abstract 2443.
  44. Mai I, Bauer S, Krueger H, et al. Wechselwirkungen von Johaniskraut mit tacrolismus bei nierentransplantierten patienten. Symposium Phytopharmaka VII. Forschung und Klinische Anwendung, Berlin, October, 2001.
  45. Bhopal JS. St John's wort-induced sexual dysfunction. Can J Psychiatry 2001;46:456-457. PubMed
  46. Schulz V. Incidence and clinical relevance of the interactions and side effects of Hypericum preparations. Phytomedicine 2001;8:152-60.
  47. Gorski JC, Hamman MA, Wang Z, et al. The effect of St. John's wort on the efficacy of oral contraceptives (abstract MPI-80). Clin Pharmacol Ther 2001;71:P25.
  48. Hennessy M, Kelleher D, Spiers JP, et al. St Johns wort increases expression of P-glycoprotein: implications for drug interactions. Br J Clin Pharmacol 2002;53:75-82.
  49. Parker V, Wong AH, Boon HS, Seeman MV. Adverse reactions to St John's Wort. Can J Psychiatry 2001;46:77-9. PubMed
  50. Patel S, Robinson R, Burk M. Hypertensive crisis associated with St. John's Wort. Am J Med 2002;112:507-8. PubMed
  51. Singhal AB, Caviness VS, Begleiter AF, et al. Cerebral vasoconstriction and stroke after use of serotonergic drugs. Neurology 2002;58:130-3. PubMed
  52. Holme SA, Roberts DL. Erythroderma associated with St John's wort. Br J Dermatol 2000;143:1127-8. PubMed
  53. Irefin S, Sprung J. A possible cause of cardiovascular collapse during anesthesia: long-term use of St. John's Wort. J Clin Anesth 2000;12:498-9. PubMed
  54. Calapai G, Crupi A, Firenzuoli F, et al. Serotonin, norepinephrine and dopamine involvement in the antidepressant action of hypericum perforatum. Pharmacopsychiatry 2001;34:45-9. PubMed
  55. Henderson L, Yue QY, Bergquist C, et al. St John's wort (Hypericum perforatum): drug interactions and clinical outcomes. Br J Clin Pharmacol 2002;54:349-56..
  56. Mathijssen RH, Verweij J, de Bruijn P, et al. Effects of St. John's wort on irinotecan metabolism. J Natl Cancer Inst 2002;94:1247-9.. PubMed
  57. Ladner DP, Klein SD, Steiner RA, Walt H. Synergistic toxicity of delta-aminolaevulinic acid-induced protoporphyrin IX used for photodiagnosis and hypericum extract, a herbal antidepressant. Br J Dermatol 2001;144:916-8. PubMed
  58. Ernst E. St. John's Wort supplements endanger the success of organ transplantation. Arch Surg 2002;137:316-9. PubMed
  59. Wang Z, Hamman MA, Huang SM, et al. Effect of St. John's wort on the pharmacokinetics of fexofenadine. Clin Pharmacol Ther 2002;71:414-20.. PubMed
  60. Chan LY, Chiu PY, Lau TK. A study of hypericin-induced teratogenicity during organogenesis using a whole rat embryo culture model. Fertil Steril 2001;76:1073-4. PubMed
  61. Schwarz UI, Buschel B, Kirch W. Unwanted pregnancy on self-medication with St John's wort despite hormonal contraception. Br J Clin Pharmacol 2003;55:112-3. PubMed
  62. Logan JL, Ahmed J. Critical hypokalemic renal tubular acidosis due to Sjogren's syndrome: association with the purported immune stimulant echinacea. Clin Rheumatol 2003;22:158-9.
  63. Mai I, Stormer E, Bauer S, et al. Impact of St John's wort treatment on the pharmacokinetics of tacrolimus and mycophenolic acid in renal transplant patients. Nephrol Dial Transplant 2003;18:819-22.. PubMed
  64. Groning R, Breitkreutz J, Muller RS. Physico-chemical interactions between extracts of Hypericum perforatum L. and drugs. Eur J Pharm Biopharm 2003;56:231-6.. PubMed
  65. Sugimoto K, Ohmori M, Tsuruoka S, et al. Different effects of St John's wort on the pharmacokinetics of simvastatin and pravastatin. Clin Pharmacol Ther 2001;70:518-24.. DOI
  66. Bauer S, Stormer E, Johne A, et al. Alterations in cyclosporin A pharmacokinetics and metabolism during treatment with St John's wort in renal transplant patients. Br J Clin Pharmacol 2003;55:203-11.. PubMed
  67. Markowitz JS, Donovan JL, DeVane CL, et al. Effect of St. John's wort on drug metabolism by induction of cytochrome P450 3A4 enzyme. JAMA 2003;290:1500-4.. PubMed
  68. Hypericum Depression Trial Study Group. Effect of Hypericum perforatum (St. John's wort) in major depressive disorder: a randomized controlled trial. JAMA 2002;287:1807-14. PubMed
  69. Hammerness P, Basch E, Ulbricht C, et al. St. John's wort: a systematic review of adverse effects and drug interactions for the consultation psychiatrist. Psychosomatics 2003;44:271-82. PubMed
  70. Gurley BJ, Gardner SF, Hubbard MA, et al. Cytochrome P450 phenotypic ratios for predicting herb-drug interactions in humans. Clin Pharmacol Ther 2002;72:276-87.. PubMed
  71. Foster BC, Vandenhoek S, Hana J, et al. In vitro inhibition of human cytochrome P450-mediated metabolism of marker substrates by natural products. Phytomedicine 2003;10:334-42.. PubMed
  72. Kim RB. Drugs as P-glycoprotein substrates, inhibitors, and inducers. Drug Metab Rev 2002;34:47-54. PubMed
  73. Dean AJ, Moses GM, Vernon JM. Suspected withdrawal syndrome after cessation of St. John's wort. Ann Pharmacother 2003;37:150. PubMed
  74. Morimoto T, Kotegawa T, Tsutsumi K, et al. Effect of St. John's wort on the pharmacokinetics of theophylline in healthy volunteers. J Clin Pharmacol 2004;44:95-101. PubMed
  75. Pfrunder A, Schiesser M, Gerber S, et al. Interaction of St John's wort with low-dose oral contraceptive therapy: a randomized controlled trial. Br J Clin Pharmacol 2003;56:683-90. PubMed
  76. Hall SD, Wang Z, Huang SM, et al. The interaction between St John's wort and an oral contraceptive. Clin Pharmacol Ther 2003;74:525-35. PubMed
  77. Frye RF, Fitzgerald SM, Lagattuta TT, et al. Effect of St. John's wort on imatinib mesylate pharmacokinetics. Clin Pharmacol Ther 2004;76:323-9. PubMed
  78. Komoroski BJ, Zhang S, Cai H, et al. Induction and inhibition of cytochromes P450 by the St. John's wort constituent hyperforin in human hepatocyte cultures. Drug Metab Dispos 2004;32:512-8. PubMed
  79. Jiang X, Williams KM, Liauw WS, et al. Effect of St John's wort and ginseng on the pharmacokinetics and pharmacodynamics of warfarin in healthy subjects. Br J Clin Pharmacol 2004;57:592-9. PubMed
  80. Shimizu K, Nakamura M, Isse K, Nathan PJ. First-episode psychosis after taking an extract of Hypericum perforatum (St John's Wort). Hum Psychopharmacol 2004;19:275-6.
  81. Szegedi A, Kohnen R, Dienel A, Kieser M. Acute treatment of moderate to severe depression with hypericum extract WS 5570 (St John's wort): randomised controlled double blind non-inferiority trial versus paroxetine. BMJ 2005;330:503. PubMed
  82. Lau WC, Carville DGM, Guyer KE, et al. St. John's Wort Enhances the Platelet Inhibitory Effect of Clopidogrel in Clopidogrel "Resistant" Healthy Volunteers. American College of Cardiology Annual Meeting, Orlando, FL 2005: Presentation 1043-129.
  83. Murphy PA, Kern SE, Stanczyk FZ, Westhoff CL. Interaction of St. John's Wort with oral contraceptives: effects on the pharmacokinetics of norethindrone and ethinyl estradiol, ovarian activity and breakthrough bleeding. Contraception 2005;71:402-8. PubMed
  84. Linde K, Knuppel L. Large-scale observational studies of hypericum extracts in patients with depressive disorders - a systematic review. Phytomedicine 2005;12:148-57. PubMed
  85. Dasgupta A, Hovanetz M, Olsen M, et al. Drug-herb interaction: effect of St John's wort on bioavailability and metabolism of procainamide in mice. Arch Pathol Lab Med 2007;131:1094-8. PubMed
  86. Dugoua JJ, Mills E, Perri D, Koren G. Safety and efficacy of St. John's wort (hypericum) during pregnancy and lactation. Can J Clin Pharmacol 2006;13:e268-76.
  87. Jiang X, Blair EY, McLachlan AJ. Investigation of the effects of herbal medicines on warfarin response in healthy subjects: a population pharmacokinetic-pharmacodynamic modeling approach. J Clin Pharmacol 2006;46:1370-8. PubMed
  88. Niederhofer H. St. John's wort may diminish methylphenidate's efficacy in treating patients suffering from attention deficit hyperactivity disorder. Med Hypotheses 2007;68:1189. PubMed
  89. Bell EC, Ravis WR, Lloyd KB, Stokes TJ. Effects of St. John's wort supplementation on ibuprofen pharmacokinetics. Ann Pharmacother 2007;41:229-34. PubMed
  90. Booth JN, McGwin G. The association between self-reported cataracts and St. John's Wort. Curr Eye Res 2009;34:863-6. PubMed
  91. Samadi S, Khadivzadeh T, Emami A, et al. The effect of Hypericum perforatum on the wound healing and scar of cesarean. J Altern Complement Med 2010;16:113-7.
  92. Wang LS, Zhu B, Abd El-Aty A, et al. The influence of St. John's wort on CYP2C19 activity with respect to genotype. J Clin Pharmacol 2004;44:577-81. PubMed
  93. Weber W, Vander Stoep A, McCarty RL, et al. Hypericum perforatum (St John's wort) for attention-deficit/hyperactivity disorder in children and adolescents: a randomized controlled trial. JAMA 2008;299:2633-41. PubMed
  94. Lee, A., Minhas, R., Matsuda, N., Lam, M., and Ito, S. The safety of St. John's wort (Hypericum perforatum) during breastfeeding. J Clin Psychiatry 2003;64(8):966-968.
  95. Eich-Hochli, D., Oppliger, R., Golay, K. P., Baumann, P., and Eap, C. B. Methadone maintenance treatment and St. John's Wort - a case report. Pharmacopsychiatry 2003;36(1):35-37. PubMed
  96. Smith M, Lin KM, and Zheng YP. PIII-89 an open trial of nifedipine-herb interactions: Nifedipine with St. John's wort, ginseng or ginkgo biloba. Clin Pharm Ther 2001;69:P86.
  97. Kawaguchi, A., Ohmori, M., Tsuruoka, S., Nishiki, K., Harada, K., Miyamori, I., Yano, R., Nakamura, T., Masada, M., and Fujimura, A. Drug interaction between St John's Wort and quazepam. Br.J.Clin Pharmacol. 2004;58(4):403-410. PubMed
  98. Dresser, G. K., Schwarz, U. I., Wilkinson, G. R., and Kim, R. B. Coordinate induction of both cytochrome P4503A and MDR1 by St John's wort in healthy subjects. Clin Pharmacol Ther 2003;73(1):41-50. PubMed
  99. Patel, J., Buddha, B., Dey, S., Pal, D., and Mitra, A. K. In vitro interaction of the HIV protease inhibitor ritonavir with herbal constituents: changes in P-gp and CYP3A4 activity. Am.J.Ther. 2004;11(4):262-277. PubMed
  100. Xu, H., Williams, K. M., Liauw, W. S., Murray, M., Day, R. O., and McLachlan, A. J. Effects of St John's wort and CYP2C9 genotype on the pharmacokinetics and pharmacodynamics of gliclazide. Br.J.Pharmacol. 2008;153(7):1579-1586.
  101. Wang, L. S., Zhou, G., Zhu, B., Wu, J., Wang, J. G., Abd El-Aty, A. M., Li, T., Liu, J., Yang, T. L., Wang, D., Zhong, X. Y., and Zhou, H. H. St John's wort induces both cytochrome P450 3A4-catalyzed sulfoxidation and 2C19-dependent hydroxylation of omepr
  102. Hojo, Y., Echizenya, M., Ohkubo, T., and Shimizu, T. Drug interaction between St John's wort and zolpidem in healthy subjects. J.Clin.Pharm.Ther. 2011;36(6):711-715. PubMed
  103. Izzo, A. A. and Ernst, E. Interactions between herbal medicines and prescribed drugs: an updated systematic review. Drugs 2009;69(13):1777-1798. PubMed
  104. Barbenel, D. M., Yusufi, B., O'Shea, D., and Bench, C. J. Mania in a patient receiving testosterone replacement postorchidectomy taking St John's wort and sertraline. J Psychopharmacol 2000;14(1):84-86.
  105. Ratz, A. E., von Moos, M., and Drewe, J. [St. John's wort: a pharmaceutical with potentially dangerous interactions]. Schweiz Rundsch.Med Prax. 5-10-2001;90(19):843-849.
  106. Guzelcan, Y., Scholte, W. F., Assies, J., and Becker, H. E. [Mania during the use of a combination preparation with St. John's wort (Hypericum perforatum)]. Ned.Tijdschr.Geneeskd. 10-6-2001;145(40):1943-1945.
  107. van Gurp, G., Meterissian, G. B., Haiek, L. N., McCusker, J., and Bellavance, F. St John's wort or sertraline? Randomized controlled trial in primary care. Can Fam Physician 2002;48:905-912.
  108. Lecrubier, Y., Clerc, G., Didi, R., and Kieser, M. Efficacy of St. John's wort extract WS 5570 in major depression: a double-blind, placebo-controlled trial. Am J Psychiatry 2002;159(8):1361-1366. PubMed
  109. Schempp, C. M., Winghofer, B., Muller, K., Schulte-Monting, J., Mannel, M., Schopf, E., and Simon, J. C. Effect of oral administration of Hypericum perforatum extract (St. John's Wort) on skin erythema and pigmentation induced by UVB, UVA, visible light
  110. Zullino, D. and Borgeat, F. Hypertension induced by St. John's Wort - a case report. Pharmacopsychiatry 2003;36(1):32. PubMed
  111. Nanayakkara, P. W., Meijboom, M., and Schouten, J. A. [Suicidal and aggressive thoughts as a result of taking a Hypericum preparation (St. John's wort)]. Ned.Tijdschr.Geneeskd. 6-11-2005;149(24):1347-1349.
  112. Fava, M., Alpert, J., Nierenberg, A. A., Mischoulon, D., Otto, M. W., Zajecka, J., Murck, H., and Rosenbaum, J. F. A Double-blind, randomized trial of St John's wort, fluoxetine, and placebo in major depressive disorder. J.Clin.Psychopharmacol. 2005;25(5 PubMed
  113. Gastpar, M., Singer, A., and Zeller, K. Comparative efficacy and safety of a once-daily dosage of hypericum extract STW3-VI and citalopram in patients with moderate depression: a double-blind, randomised, multicentre, placebo-controlled study. Pharmacops PubMed
  114. Cappuzzo, K. A. Herbal product use in a patient with polypharmacy. Consult Pharm. 2006;21(11):911-915. PubMed
  115. Papakostas, G. I., Crawford, C. M., Scalia, M. J., and Fava, M. Timing of clinical improvement and symptom resolution in the treatment of major depressive disorder. A replication of findings with the use of a double-blind, placebo-controlled trial of Hyp DOI
  116. Sardella, A., Lodi, G., Demarosi, F., Tarozzi, M., Canegallo, L., and Carrassi, A. Hypericum perforatum extract in burning mouth syndrome: a randomized placebo-controlled study. J.Oral Pathol.Med. 2008;37(7):395-401.
  117. Etogo-Asse, F., Boemer, F., Sempoux, C., and Geubel, A. Acute hepatitis with prolonged cholestasis and disappearance of interlobular bile ducts following tibolone and Hypericum perforatum (St. John's wort). Case of drug interaction? Acta Gastroenterol.Be
  118. Andreescu, C., Mulsant, B. H., and Emanuel, J. E. Complementary and alternative medicine in the treatment of bipolar disorder--a review of the evidence. J.Affect.Disord. 2008;110(1-2):16-26. PubMed
  119. Kasper, S., Volz, H. P., Moller, H. J., Dienel, A., and Kieser, M. Continuation and long-term maintenance treatment with Hypericum extract WS 5570 after recovery from an acute episode of moderate depression--a double-blind, randomized, placebo controlled
  120. Al-Akoum, M., Maunsell, E., Verreault, R., Provencher, L., Otis, H., and Dodin, S. Effects of Hypericum perforatum (St. John's wort) on hot flashes and quality of life in perimenopausal women: a randomized pilot trial. Menopause. 2009;16(2):307-314. PubMed
  121. Brattstrom, A. Long-term effects of St. John's wort (Hypericum perforatum) treatment: a 1-year safety study in mild to moderate depression. Phytomedicine. 2009;16(4):277-283. PubMed
  122. Canning, S., Waterman, M., Orsi, N., Ayres, J., Simpson, N., and Dye, L. The efficacy of Hypericum perforatum (St John's wort) for the treatment of premenstrual syndrome: a randomized, double-blind, placebo-controlled trial. CNS.Drugs 2010;24(3):207-225. PubMed
  123. Van Strater, A. C. and Bogers, J. P. Interaction of St John's wort (Hypericum perforatum) with clozapine. Int.Clin.Psychopharmacol. 2012;27(2):121-124. PubMed
  124. Sultana D, Peindl KS Wisner KL. Rash associated with St. John's wort treatment in premenstrual dysphoric disorder. Arch Women Ment Health 2000;3:99-101. DOI
  125. Bernd A, Ramirez-Bosca A, Kippenberger S, and et al. Phototoxic effects of Hypericum extract in cultures of human keratinocytes compared with those of psoralen. Photochem Photobiol 1999;2(69):218-221.
  126. Woelk H, Burkard G, and Grunwald J. Nutzen und Risikobewertung des Hypericum-extraktes LI 160 auf der Basis einer Drug-Monitoring-Studie mit 3250 patienten. Nervenheilkunde 1993;12:308-313.
  127. Schakau D, Hiller K, Schultz-Zehden W, and et al. Risk/benefit profile of St.John's wort extract: STEI 300 in 2404 patients with various degrees of psychiatric disturbance. Psychopharmakotherapie 1996;3:116-122.
  128. Laird RD and Webb M. Psychotic episode during use of St John's wort. J Herbal Pharmacother 2001;1(2):81-87. DOI
  129. Schrader E, Meier B, and Brattstrom A. Hypericum treatment of mild-moderate depression in a placebo-controlled study. A prospective, double-blind, randomized, placebo-controlled, multicentre study. Human Psychopharm 1998;13:163-169. DOI
  130. Dolton MJ, Mikus G, Weiss J, et al. Understanding variability with voriconazole using a population pharmacokinetic approach: implications for optimal dosing. J Antimicrob Chemother 2014;69(6):1633-41. PubMed
  131. Goey AK, Meijerman I, Rosing H, et al. The effect of St John's wort on the pharmacokinetics of docetaxel. Clin Pharmacokinet 2014;53(1):103-10. PubMed
  132. Lei HP, Yu XY, Xie HT, et al. Effect of St. John's wort supplementation on the pharmacokinetics of bupropion in healthy male Chinese volunteers. Xenobiotica 2010;40(4):275-81. PubMed
  133. Gurok MG, Mermi O, Kilic F, et al. Psychotic episode induced by St. John's wort (Hypericum perforatum): a case report. J Mood Dis 2014;4(1):38-40. DOI
  134. Yildirim O, Canan F. A case of panic attack induced by St John's wort. Prim Care Companion CNS Disord 2013;15(1). pii: PCC.12l01453. PubMed
  135. Abdali K, Khajehei M, Tabatabaee HR. Effect of St John's wort on severity, frequency, and duration of hot flashes in premenopausal, perimenopausal and postmenopausal women: a randomized, double-blind, placebo-controlled study. Menopause 2010;17(2):326-31. PubMed
  136. Trana C, Toth G, Wijns W, Barbato E. St. John's Wort in patients non-responders to clopidogrel undergoing percutaneous coronary intervention: a single-center randomized open-label trial (St. John's Trial). J Cardiovasc Transl Res 2013;6(3):411-4. PubMed
  137. Agollo MC, Miszputen SJ, Diament J. Hypericum perforatum-induced hepatotoxicity with possible association with copaiba (copaifera langsdorffii desf): a case report. Einstein (Sao Paulo) 2014;12(3):355-7.
  138. Hohmann N, Maus A, CarlsA, Haefeli WE, Mikus G. St. John's wort treatment in women bears risks beyond pharmacokinetic drug interactions. Arch Toxico. 2016;90(4):1013-15. doi:10.1007/s00204-015-1532-7. PubMed
  139. Jackson A, D'Avolio A, Moyle G, et al. Pharmacokinetics of the co-administration of boceprevir and St. John's wort to male and female healthy volunteers. J Antimicrob Chemother 2014;69:1911-1915. PubMed
  140. Jones D. Tourian LT, Margolese H. Possible association of syndrome of Inappropriate secretion of antidiuretic hormone with St. John's wort use. J of Clin Psychopharmacol 2014:34(6):759-60. PubMed
  141. Soleymani S, Bahramsoltani R, Rahimi R, Abdollahi M. Clinical risks of St John's Wort (Hypericum perforatum) co-administration. Expert Opin Drug Metab Toxicol. 2017;13(10):1047-62.
  142. Chrubasik-Hausmann S, Vlachojannis J, McLachlan AJ. Understanding drug interactions with St John's wort (Hypericum perforatum L.): impact of hyperforin content. J Pharm Pharmacol. 2018.
  143. Market C, Kastner IM, Hellwig, et al. The effect of induction of CYP3A4 by St. John's wort on ambrisentan plasma kinetics in volunteers of known CY2C19 genotype. Basic & Clinical Pharmacology & Toxicology 2015;116:423-428.
  144. Loughren MJ, Kharasch ED, Kelton-Rehkopf MC, Syrjala KL, Shen DD. Influence of St. John's wort on intravenous fentanyl pharmacokinetics, pharmacodynamics, and clinical effects: a randomized clinical trial. Anesthesiology 2020;132(3):491-503. PubMed
  145. Scholz I, Liakoni E, Hammann F, et al. Effects of Hypericum perforatum (St. John's wort) on the pharmacokinetics and pharmacodynamics of rivaroxaban in humans. Br J Clin Pharmacol. 2020. doi: 10.1111/bcp.14553.
  146. Fisher KA, Patel P, Abualula S, Concepion L. St. John's Wort-Induced Supraventricular Tachycardia. Cureus. 2021 Apr 7;13(4):e14356. PubMed
  147. Schäfer W, Wentzell N, Schink T, Haug U. Characterization of pregnancies exposed to St. John's wort and their outcomes: A claims data analysis. Reprod Toxicol. 2021 Jun;102:90-97. PubMed
  148. Adibelli Z, Karacay I, Demir M, Duran C. St. John's Wort (Hypericum perforatum)-related acute kidney injury. Blood Purif. 2021 Aug 24:1-3. doi: 10.1159/000518349.
  149. Sarris J, Ravindran A, Yatham LN, et al. Clinician guidelines for the treatment of psychiatric disorders with nutraceuticals and phytoceuticals: The World Federation of Societies of Biological Psychiatry (WFSBP) and Canadian Network for Mood and Anxiety T
  150. Haron MH, Dale O, Martin K, et al. Evaluation of the Herb-Drug Interaction Potential of Commonly Used Botanicals on the US Market with Regard to PXR- and AhR-Mediated Influences on CYP3A4 and CYP1A2. J Diet Suppl 2022. PubMed
  151. Pochet S, Lechon AS, Lescrainier C, et al. Herb-anticancer drug interactions in real life based on VigiBase, the WHO global database. Sci Rep 2022;12(1):14178. PubMed
  152. Gümüs KS, Teegelbekkers A, Sauter M, et al. Effect of Tacrolimus Formulation (Prolonged-Release vs Immediate-Release) on Its Susceptibility to Drug-Drug Interactions with St. John's Wort. Clin Pharmacol Drug Dev 2024. PubMed

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

Keep exploring
Supplement interaction checker › Check any supplement or product against your medications Drug–drug interactions › Check two or more of your medications against each other Browse medications A–Z › Every drug we've checked against herbs & supplements NDC & pricing lookup › Find a drug’s NDCs, packaging and costs Ask a pharmacist › Free, personal answer from our licensed team