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Dietary supplement

St. John's Wort Ingredients & Drug Interactions

by Wonder Laboratories

St. John's Wort label
See full label image
Capsule Category: Botanical
Most serious interaction: Major
Clinical methodology reviewed by · Updated Sep 16, 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 Wonder Laboratories with 3 active ingredients. Its ingredients are commonly taken for insomnia and poor sleep, anxiety and stress, restlessness.Based on those ingredients, 1,255 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are St. John's Wort Flower, Leaf Extract, Valerian Root Extract, Passionflower Aerial Part 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 Wonder Laboratories

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HelloPharmacist Scorecard of St. John's Wort by Wonder Laboratories

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 3 of its 3 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

This product contains three active herbal extracts. Valerian Root Extract is traditionally used to support sleep and relaxation.

St. John's Wort Flower, Leaf Extract is commonly taken for mood support.

Passionflower Aerial Part Extract is included for its calming properties. The three ingredients are combined in a capsule format with inactive ingredients—cellulose, gelatin, silica, and magnesium stearate—which serve as fillers and binders.

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: support balanced state of personal well being.
  • We looked for evidence on: Anxiety, Depression, Insomnia, Stress, Seasonal affective disorder (SAD), Menopausal symptoms — and 4 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: Valerian is rated "Possibly Effective" for Insomnia.

Valerian has possibly effective evidence for insomnia, though long-term data is limited. St.

John's Wort is likely effective for depression and possibly effective for somatic symptom disorder and menopausal symptoms, though it's possibly ineffective for HIV/AIDS and irritable bowel syndrome. Passionflower is possibly effective for insomnia and pre-procedural anxiety.

The evidence for stress, dysmenorrhea, benzodiazepine withdrawal, and alcohol use disorder is insufficient to establish whether these ingredients work for those purposes.

The evidence, ingredient by ingredient Valerian St. John's Wort Passion Flower

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 3 of the 3 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 3 of 3.
  • General safety write-ups exist for 3 of 3.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

All three ingredients are generally well tolerated short-term. Common side effects include dizziness, drowsiness, headache, and gastrointestinal upset.

Valerian may cause vivid dreams or excitability; St. John's Wort can trigger photosensitivity (sun sensitivity) and in rare cases suicidal thoughts or psychosis; passionflower may cause confusion and sedation.

When valerian is stopped abruptly after extended use, withdrawal symptoms such as anxiety, irritability, and insomnia may occur—taper slowly. Rare liver problems have been reported with valerian in combination products.

St. John's Wort is not recommended in pregnancy or while breastfeeding.

Valerian safety has not been established in pregnancy and should be avoided; breastfeeding data is insufficient, so it should be avoided as well. Passionflower should be avoided in pregnancy due to lack of safety data and possible effects on the uterus, and avoided while breastfeeding.

Side effects, ingredient by ingredient Valerian St. John's Wort Passion Flower

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?
  • 3 of the 3 matched ingredients can interact with medications — St. John's Wort, Valerian, Passion Flower.
  • 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: 1,256 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 any digoxin, phenobarbital, phenytoin, irinotecan, protease inhibitors, tacrolimus, or docetaxel (Major interactions with St. John's Wort); CNS depressants like benzodiazepines or sleeping pills, or if you drink alcohol (Moderate interactions with valerian and passionflower); or alprazolam specifically (Moderate interaction with valerian).

Use the medication checker on this page to verify your prescriptions.

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.

This product combines three herbal ingredients with sedative and mood-supporting properties. It's worth considering if you're looking for natural sleep or stress support—but only if you don't take digoxin, seizure medications, cancer drugs, HIV medications, immunosuppressants, CNS depressants (like sleeping pills or tranquilizers), or drink alcohol regularly.

Run your exact medications through the checker on this page before you start. Not for pregnancy or breastfeeding.

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

Assessment coverage: 3 of 3 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Aug 22, 2024.

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 Wonder Laboratories
Barcode (UPC) 099528272242
Net contents 240 Capsule(s)
Market status On market
Date entered into DSLD Aug 22, 2024
DSLD ID 315252
Product type Botanical
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Gluten 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 Wonder Laboratories, 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:
2 Capsule(s)
Servings per container
240
UPC/BARCODE
099528272242
IngredientAmount% DV
Valerian Root Extract15 mg--
St. John's Wort Flower, Leaf Extract300 mg--
Passionflower Aerial Part Extract15 mg--

Other ingredients: Cellulose, Gelatin, Silica, Magnesium Stearate

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.
Formula

St. John's Wort is very popular in Europe where it is favored for its ability to support a balanced state of personal well being. This assured potency formulation is made from the same type of St. John's Wort extract used in major research studies. Our extract contains 0.3% hypericin, the same level of this important constituent used in clinical trials. Concentrated, standardized extracts of Valerian root and Passion Flower herb are added to the standardized St. John's Wort extract to optimize the natural benefits of this exceptional dietary supplement. This balanced approach to formulation of dietary supplements ensures all naturally occurring constituents are available.

0.3% Hypericin

Formulation

Mfg. in an FDA Registered Facility using Good Manufacturing Practices (GMPs)

Conforms to USP <2091> for weight. Meets USP <2040> disintegration for maximum bioavailability.

Standardized assured potency The "Mood Herb" Supports a balanced state of personal well being

Gluten free

Made in USA

Precautions

Tamper evident: Do not use this product if imprinted foil seal under cap is broken or missing.

Warning: Use sunscreen during exposure to the sun while using this product.

If you are pregnant, nursing or taking any prescription medication consult your doctor before taking this product.

Keep out of reach of children.

Storage

Keep tightly closed. Store at room temperature 59 Degrees - 86 Degrees F (15 Degrees to 30 Degrees C).

FDA Disclaimer Statement

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

General Statements

Rev. #01 Formula 272

FDA Statement of Identity

Dietary Supplement

Suggested/Recommended/Usage/Directions

Directions: Take 1 to 2 capsules one to three times daily.

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 Wonder Laboratories 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 Wonder Laboratories

These are the 3 active ingredients this product is made of. Select any to open its full monograph.

Serving size1 Capsule(s) Dosage formCapsule Servings per container240 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.

Valerian Root Extract

Interacts with
902 drugs
15 mg per serving

Valerian is an herb whose root is widely used as a natural sleep aid and for calming nerves. The evidence is mixed and often weak, so it may help some...

Valerian Root Extract monograph & interactions

St. John's Wort Flower, Leaf Extract

Interacts with
1,143 drugs
300 mg per serving Form: St. John's Wort Flower Extract, St. John's Wort Leaf Extract

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, Leaf Extract monograph & interactions

Passionflower Aerial Part Extract

Interacts with
836 drugs
15 mg per serving

Passion flower is a traditional calming herb that many people use for anxiety and sleep. Early studies hint it may help with mild anxiety and restless...

Passionflower Aerial Part Extract monograph & interactions

Other (inactive) ingredients: Cellulose, Gelatin, Silica, Magnesium Stearate. These complete the product’s ingredient list but are not active constituents.

Interaction report

St. John's Wort by Wonder Laboratories 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
1,255Drugs
755 Major 476 Moderate 24 Minor

Ingredients driving the most interactions

St. John's Wort Flower, Leaf Extract 1,143
Valerian Root Extract 902
Passionflower Aerial Part Extract 836

Individual Drug Interactions

The ingredients in St. John's Wort interact with 1,255 drugs. Click any drug to see the details.

3 of the 3 ingredients in St. John's Wort interact with drugs. Each result below shows which ingredient is responsible. St. John's Wort Flower, Leaf Extract Valerian Root Extract Passionflower Aerial Part 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 they can affect. Open any type for the detail — or search your exact drug in the checker above.

St. John's Wort Flower, Leaf 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, Leaf Extract full monograph & all 47 interactions

Valerian Root Extract6 drug types · 902 drugs

Alcohol (Ethanol)

Valerian can have additive sedative effects when used concomitantly with alcohol.
Valerian has sedative effects. Theoretically, valerian might have an additive sedative effect when combined with alcohol. Excessive sedation has been reported in an alcohol-abusing individual who took valerian and Gingko biloba. However, the potential interaction between valerian and alcohol has been disputed in other research. Limited evidence suggests that a combination of valerian 160 mg and lemon balm 80 mg (Euvegal) does not cause further deterioration in reaction ability and reaction rate when taken with alcohol as compared to the effects of alcohol alone.

Likelihood Possible Evidence B
Alprazolam (Xanax)

Valerian can have additive sedative effects when used with alprazolam. Also, valerian in high doses might modestly increase alprazolam levels, though this is not likely to be clinically significant.
Valerian has sedative effects. Theoretically, valerian might cause additive sedation when combined with alprazolam. Also, a small pharmacokinetic study shows that taking valerian extract 1000 mg daily (providing 11 mg valerenic acid) might increase alprazolam levels by about 19%. This might be due to valerian's mild inhibition of cytochrome P450 3A4 (CYP3A4). Despite being statistically significant, this increase is not likely to be clinically significant.

Likelihood Possible Evidence B
Cns Depressants

Valerian can have additive sedative effects when used concomitantly with CNS depressant drugs.
Theoretically, concomitant use of valerian and drugs with sedative and anesthetic properties may cause additive therapeutic and adverse effects.

Likelihood Possible Evidence D
Glucuronidated Drugs

Valerian might weakly inhibit glucuronidation and increase concentrations of drugs metabolized by UGT1A1 and UGT2B7.
In vitro research shows that methanolic valerian extract and valerenic acid might competitively inhibit UDP-glucuronosyltransferase (UGT) 1A1 (UGT1A1) and UGT2B7.

Likelihood Possible Evidence D
Cytochrome P450 2D6 (Cyp2D6) Substrates

Valerian does not seem to have a clinically relevant effect on levels of drugs metabolized by CYP2D6.
Although some in vitro evidence suggests that valerian affects CYP2D6, clinical pharmacokinetic (PK) studies show that valerian is unlikely to affect the CYP2D6 enzyme. In one PK study, taking valerian 1000 mg (providing about 11 mg valerenic acid) nightly for 14 days did not affect the metabolism of dextromethorphan, a CYP2D6 substrate. In another PK study, taking valerian 125 mg three times daily for 28 days did not affect metabolism of debrisoquine, an accepted CYP2D6 probe-substrate.

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

Valerian does not seem to have a clinically relevant effect on levels of drugs metabolized by CYP3A4.
Although some in vitro evidence suggests that valerian extract might inhibit or induce CYP3A4, clinical pharmacokinetic (PK) studies show that valerian does not have a clinically significant effect on the CYP3A4 enzyme. In one PK study, taking valerian 125 mg three times daily for 28 days did not affect metabolism of midazolam, an accepted CYP3A4 probe-substrate. In another PK study, taking valerian 1000 mg (providing about 11 mg valerenic acid) nightly for 14 days modestly increases levels of alprazolam, a CYP3A4 substrate, suggesting mild inhibition of CYP3A4. However, this mild inhibition is unlikely to be clinically relevant.

Likelihood Possible Evidence B
Valerian Root Extract full monograph & interactions

Passionflower Aerial Part Extract3 drug types · 836 drugs

Cns Depressants

Concomitant use of passion flower with sedative drugs might cause additive effects and side effects.
Research in animals and humans shows that passion flower has sedative effects which can be additive when used with sedative medications like lorazepam.

Likelihood Possible Evidence D
Cytochrome P450 3A4 (Cyp3A4) Substrates

Theoretically, passion flower might decrease the effects of CYP3A4 substrates.
In vitro research suggests that passion flower can induce CYP3A4 enzymes, albeit to a much lower degree than rifampin, a known CYP3A4 inducer.

Likelihood Possible Evidence D
Organic Anion-Transporting Polypeptide Substrates (Oatp)

Theoretically, passion flower might reduce the bioavailability of OATP2B1 and OATP1A2 substrates.
In vitro research shows that the passion flower constituents apigenin and vitexin inhibit OATP2B1 and OATP1A2. This inhibition may be dose-dependent. One specific high-flavonoid passion flower extract (Valverde) seems to inhibit OATP2B1 and OATP1A2, while another extract with a lower flavonoid concentration (Arkocaps) shows less potent inhibition. OATPs are responsible for the uptake of drugs and other compounds into the body; however, the specific activities of OATP2B1 and OATP1A2 are not well characterized.

Likelihood Possible Evidence D
Passionflower Aerial Part Extract full monograph & interactions
The maker

Brand information

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

Wonder Laboratories

See all Wonder Laboratories products
Name
Wonder Laboratories
Street Address
115 S.C.T. Ct.
City
White House
State
TN
ZipCode
37188
Pharmacist Counseling Corner

St. John's Wort by Wonder Laboratories: Common Questions

Does St. John's Wort by Wonder Laboratories interact with any medications?
Yes. Based on its ingredients, St. John's Wort has a known interaction with 1,255 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 3 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.
Will this help me sleep?
Valerian and passionflower each have possibly effective evidence for insomnia, so they may help you fall asleep or stay asleep. St. John's Wort isn't studied for sleep directly. Results vary person to person, and the safety data is strongest for short-term use.
Can I take this if I'm on a blood thinner or heart medication?
Not without checking with your pharmacist first. St. John's Wort significantly reduces digoxin levels, a common heart medication, and can interfere with many other drugs. Your specific medications need to be screened before you start.
What are the most common side effects?
Dizziness, drowsiness, headache, and mild stomach upset are most frequently reported. St. John's Wort can make your skin more sensitive to sun exposure. If you stop valerian abruptly after taking it for a long time, you may experience withdrawal symptoms like anxiety or insomnia—taper your dose slowly instead.
Is it safe to take this while pregnant or breastfeeding?
No. St. John's Wort and passionflower don't have enough safety data and should be avoided in pregnancy. Valerian is best avoided during pregnancy as well. None of the three should be used while breastfeeding.
Can I drink alcohol with this?
Not safely. Valerian can have additive sedative effects with alcohol, meaning you may become much drowsier or more impaired than either alone would cause. Skip alcohol while taking this product.
How long can I safely take this?
Long-term safety isn't well studied for any of these three ingredients. The safety data is strongest for short-term use. Talk with your pharmacist about how long you plan to take it and whether you should monitor anything.

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

Valerian

Interacts with 902 drugs

Valerian is an herb whose root is widely used as a natural sleep aid and for calming nerves. The evidence is mixed and often weak, so it may help some people sleep but does not work reliably...

Read the full Valerian monograph → 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 → Herb & supplement monograph

Passion Flower

Interacts with 836 drugs

Passion flower is a traditional calming herb that many people use for anxiety and sleep. Early studies hint it may help with mild anxiety and restlessness, but the evidence is limited and mo...

Read the full Passion Flower 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 208 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.

Valerian 37 references
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  3. Klepser TB, Klepser ME. Unsafe and potentially safe herbal therapies. Am J Health Syst Pharm 1999;56:125-38. PubMed
  4. Houghton PJ. The scientific basis for the reputed activity of Valerian. J Pharm Pharmacol 1999;51:505-12. PubMed
  5. Garges HP, Varia I, Doraiswamy PM. Cardiac complications and delirium associated with Valerian root withdrawal. [Letter to the Editor]. JAMA 1998;280:1566-7. PubMed
  6. Budzinski JW, Foster BC, Vandenhoek S, Arnason JT. An in vitro evaluation of human cytochrome P450 3A4 inhibition by selected commercial herbal extracts and tinctures. Phytomedicine 2000;7:273-82. PubMed
  7. MacGregor FB, Abernethy VE, Dahabra S, et al. Hepatotoxicity of herbal remedies. BMJ 1989;299:1156-7. PubMed
  8. Leathwood PD, Chauffard F. Aqueous extract of valerian reduces latency to fall asleep in man. Planta Med 1985;2:144-8. PubMed
  9. Hadley S, Petry JJ. Valerian. Am Fam Physician 2003;67:1755-8..
  10. Glass JR, Sproule BA, Herrmann N, et al. Acute pharmacological effects of temazepam, diphenhydramine, and valerian in healthy elderly subjects. J Clin Psychopharmacol 2003;23:260-8. PubMed
  11. Lefebvre T, Foster BC, Drouin CE, et al. In vitro activity of commercial valerian root extracts against human cytochrome P450 3A4. J Pharm Pharmaceut Sci 2004;7:265-73.
  12. Yuan CS, Mehendale S, Xiao Y, et al. The gamma-aminobutyric acidergic effects of valerian and valerenic acid on rat brainstem neuronal activity. Anesth Analg 2004;98:353-8. PubMed
  13. Donovan JL, DeVane CL, Chavin KD, et al. Multiple night-time doses of valerian (Valeriana officinalis) had minimal effects on CYP3A4 activity and no effect on CYP2D6 activity in healthy volunteers. Drug Metab Dispos 2004;32:1333-6. PubMed
  14. Gurley BJ, Gardner SF, Hubbard MA, et al. In vivo effects of goldenseal, kava kava, black cohosh, and valerian on human cytochrome P450 1A2, 2D6, 2E1, and 3A4/5 phenotypes. Clin Pharmacol Ther 2005;77:415-26. PubMed
  15. Gutierrez S, Ang-Lee MK, Walker DJ, Zacny JP. Assessing subjective and psychomotor effects of the herbal medication valerian in healthy volunteers. Pharmacol Biochem Behav 2004;78:57-64. PubMed
  16. Jacobs BP, Bent S, Tice JA, et al. An internet-based randomized, placebo-controlled trial of kava and valerian for anxiety and insomnia. Medicine (Baltimore) 2005;84:197-207. PubMed
  17. National Toxicology Program, US Department of Health and Human Services. Chemical Information Review Document for Valerian (Valeriana officinalis L.) [CAS No. 8057-49-6] and Oils [CAS No. 8008-88-6]. Supporting Nomination for Toxicological Evaluation by t
  18. Fernández-San-Martín MI, Masa-Font R, Palacios-Soler L, et al. Effectiveness of Valerian on insomnia: a meta-analysis of randomized placebo-controlled trials. Sleep Med. 2010 Jun;11:505-11. PubMed
  19. Coxeter PD, Schluter PJ, Eastwood HL, et al. Valerian does not appear to reduce symptoms for patients with chronic insomnia in general practice using a series of randomised n-of-1 trials. Complement Ther Med. 2003 Dec;11:215-22. PubMed
  20. Diaper A, Hindmarch I. A double-blind, placebo-controlled investigation of the effects of two doses of a valerian preparation on the sleep, cognitive and psychomotor function of sleep-disturbed older adults. Phytother Res. 2004 Oct;18:831-6. PubMed
  21. Cuellar NG, Ratcliffe SJ. Does valerian improve sleepiness and symptom severity in people with restless legs syndrome? Altern Ther Health Med 2009;15:22-8.
  22. Chen D, Klesmer J, Giovanniello A, et al. Mental status changes in an alcohol abuser taking valerian and gingko biloba. Am J Addict. 2002 Winter;11:75-7. PubMed
  23. Albrecht M, Berger W, Laux P, Schmidt U, et al. Psychopharmaka und Verkehrssicherheit. Der Einfluß von Euvegal&reg; - Dragees forte auf die Fahrtüchtigkeit und Kombinationswirkungen mit Alkohol Z Allg Med 1995;71:1215-25.
  24. Carrasco MC, Vallejo JR, Pardo-de-Santayana M, et al. Interactions of Valeriana officinalis L. and Passiflora incarnata L. in a patient treated with lorazepam. Phytother Res. 2009 Dec;23:1795-6.
  25. Hellum BH, Nilsen OG. The in vitro inhibitory potential of trade herbal products on human CYP2D6-mediated metabolism and the influence of ethanol. Basic Clin Pharmacol Toxicol. 2007 Nov;101:350-8.
  26. Hellum BH, Hu Z, Nilsen OG. The induction of CYP1A2, CYP2D6 and CYP3A4 by six trade herbal products in cultured primary human hepatocytes. Basic Clin Pharmacol Toxicol. 2007 Jan;100:23-30. PubMed
  27. Alkharfy, K. M. and Frye, R. F. Effect of valerian, valerian/hops extracts, and valerenic acid on glucuronidation in vitro. Xenobiotica 2007;37(2):113-123.
  28. Vassiliadis, T., Anagnostis, P., Patsiaoura, K., Giouleme, O., Katsinelos, P., Mpoumponaris, A., and Eugenidis, N. Valeriana hepatotoxicity. Sleep Med 2009;10(8):935. PubMed
  29. Muller, Z., Sarkany, A., Altorjay, A., Szilagyi, A., Tura, T., and Ozsvar, Z. [Liver failure a la Eastern Europe]. Orv.Hetil. 3-22-2009;150(12):555-557. PubMed
  30. National Toxicology Program, US Department of Health and Human Services. Chemical Information Review Document for Valerian (Valeriana officinalis L.) [CAS No. 8057-49-6] and Oils [CAS No. 8008-88-6]. 2009;
  31. Wells SR. International intravenous administration of a crude valerian root extract. NACCT 1995;33:542.
  32. Aydinoglu U, Özcan H, Yücel A, Yücel N, Mutlu M. Valerian induced hypomania: a case report. Bull Clin Psychopharma 2012;22(Suppl. 1):S63.
  33. Mirabi P, Mojab F. The effects of valerian root on hot flashes in menopausal women. Iran J Pharm Res 2013;12(1):217-22.
  34. Thomas K, Canedo J, Perry PJ, et al. Effects of valerian on subjective sedation, field sobriety testing and driving simulator performance. Accid Anal Prev. 2016 Jul;92:240-4. PubMed
  35. Kia YH, Alexander S, Dowling D, Standish R. A case of steroid-responsive valerian-associated hepatitis. Intern Med J. 2016 Jan;46(1):118-9. PubMed
  36. Burke H, Jiang S, Chatham P, Stern TA. Delirium After Withdrawal From Valerian Root: A Case Report. Psychosomatics. 2020;61(6):787-790. PubMed
  37. Hajizadeh I, Jamshidi M, Kazemi M, Kargar H, Sadeghi T. Comparison the effect of valerian and gabapentin on RLS and sleep quality in hemodialysis patients: A randomized clinical trial. Ther Apher Dial 2023.

See these in context on the Valerian monograph →

St. John's Wort 152 references
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  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
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  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.
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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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