St. John's wort

St. John's wort is used for Mild or moderate depression, Menopause symptoms and Somatic symptom disorder.

Also called: Bm Hypericum (United States)

Pronunciation: pronunciation varies by local usage.

Generic name: St. John's wort
Drug class: Herbal product marketed as a dietary supplement in the United States
Form: Sold as a dietary supplement in the United States; marketed as tablets, capsules, powders, teas, extracts, and fresh or dried plants
Route: Oral and topical (application to the skin) use are both described by the sources
Legal status: Marketed as a dietary supplement. Unlike drugs, dietary supplements are not approved by the U.S. Food and Drug Administration (FDA) before they are sold to the public. It is widely prescribed for depression in Europe.

Availability and supply rules vary by country

Trade names by country: United States

What St. John's wort is and how it works

St. John's wort is a plant with yellow flowers that has been widely used in various systems of traditional medicine, including Greek, Islamic, and Chinese medicine. Its name apparently refers to John the Baptist, as the plant blooms around the time of the feast of St. John the Baptist in late June. Historically it has been used for a variety of conditions, including depression, stomach ulcers, and colds, and to aid wound healing. Currently it is most widely promoted for symptoms of depression, and it is also promoted for menopause symptoms and other conditions. Topical use is promoted for wounds and other skin conditions. (1) (2)

Many studies have been done on St. John's wort for depression, and their results indicate that it may be helpful for mild or moderate depression, but the evidence is mixed and it isn't consistently effective. For other conditions, the evidence is insufficient to allow definite conclusions. It has been clearly shown that St. John's wort can interact in dangerous, sometimes life-threatening ways with a variety of medicines. Do not use it to replace conventional care or to postpone seeing your health care provider.

Mechanism of action: how St. John's wort works

The sources describe St. John's wort as a plant, Hypericum perforatum, and as a stimulant; they describe interaction effects including weakening the effects of many medicines and increasing serotonin-related effects when combined with certain antidepressants or other serotonergic drugs. These sources do not establish a mechanism of action for depression. (1) (2)

What is St. John's wort used for?

Mild or moderate depression

Many studies have been done on the usefulness of St. John's wort for depression, and their results indicate that it may be helpful for mild or moderate depression. It appears to be more effective than a placebo and as effective as standard antidepressant medications for mild or moderate depression. It's uncertain whether this is true for severe depression or for time periods longer than 12 weeks. Elsewhere the sources state that St. John's wort isn't consistently effective for depression and that results of studies on its effectiveness for depression are mixed. (1) (2)

Menopause symptoms

Small numbers of studies suggest that St. John's wort may be helpful for hot flashes associated with menopause. St. John's wort is also promoted for menopause symptoms, but the evidence for other conditions is insufficient to allow definite conclusions. (1)

Somatic symptom disorder

Small numbers of studies suggest that St. John's wort may be helpful for somatic symptom disorder (a condition involving intense anxiety about physical symptoms). (1)

Conditions studied without clear evidence of benefit

St. John's wort has also been studied as a treatment for a variety of other conditions, including attention-deficit hyperactivity disorder (ADHD), irritable bowel syndrome, obsessive compulsive disorder, and premenstrual syndrome; as a possible aid to smoking cessation; and as an ingredient in topical preparations for wound healing. However, only a small amount of research has been done on the use of St. John's wort for each of these purposes, and the evidence hasn't clearly shown it to be helpful for any of them. (1)

Before taking St. John's wort

Do not take / not appropriate for

Do not use St. John's wort to replace conventional care or to postpone seeing your health care provider about a mental health problem. Don't try to treat depression on your own. (depression) (2)

Tell your clinician about

If you take any type of medicine, talk with your health care provider before using St. John's wort or other herbal products, because some herbs and medicines interact in harmful ways. This is especially crucial for St. John's wort because this herb interacts with so many medicines.
Tell your health care providers about any complementary health approaches you use, so you can make shared, well-informed decisions.
If you are pregnant or nursing, or are considering giving a dietary supplement to a child: many dietary supplements haven't been tested in pregnant women, nursing mothers, or children, and there is little safety information on St. John's wort for pregnant women or children.
If you or someone you know may have depression, consult a health care provider; depression can be a serious illness and for some people can increase the risk of suicide.

(1) (2) (3)

St. John's wort dosage and how to take it

These sources do not provide a dose, schedule, or duration of use for St. John's wort; no dose is established by the sources on this page.
If you are thinking about using an herbal medicine, first get information on it from reliable sources. Make sure to tell your health care provider about any herbal medicines you are taking.
Talk with your health care providers about any complementary health approaches you use, and make shared, well-informed decisions.
If you take any type of medicine, talk with your health care provider before using St. John's wort or other herbal products.

(1) (3)

Procedures and treatment changes

Tell the treating team before surgery, procedures, or any medicine change. Do not alter treatment without the responsible clinician. (1) (2) (3)

Missed dose

Not established by the sources on this page. No missed-dose guidance is provided by the research notes; ask your health care provider or pharmacist for advice rather than changing how you use the product yourself.

Overdose

Dietary supplements can cause medical problems if you use them incorrectly or in large amounts. These sources do not provide overdose amounts or specific overdose management for St. John's wort. If you may have used too much, contact a health care provider or poison-information service. (2)

St. John's wort side effects

For most adults who are not taking any kind of medicine, St. John's wort appears to be safe when used for up to 12 weeks, and some studies indicate that it can be used safely for a year or more. If taken orally in large doses or applied to the skin, it might cause severe skin reactions after sun exposure. Other side effects of St. John's wort for depression are usually minor and uncommon.

Diarrhea, dizziness, trouble sleeping, restlessness, and skin tingling

What to notice: These are listed side effects of St. John's wort taken orally.

What to do: Discuss persistent or troublesome symptoms with your health care provider rather than stopping treatment yourself. (1)

Upset stomach, dry mouth, headache, fatigue, dizziness, confusion, sexual dysfunction, sensitivity to sunlight

What to notice: Other side effects of St. John's wort for depression are usually minor and uncommon; they may include these effects.

What to do: Discuss persistent or troublesome symptoms with your health care provider rather than stopping treatment yourself. (2)

Worsening feelings of anxiety

What to notice: St. John's wort is a stimulant and may worsen feelings of anxiety in some people.

What to do: Discuss this with your health care provider. (2)

Severe skin reactions after sun exposure

What to notice: If taken orally in large doses or applied to the skin, St. John's wort might cause severe skin reactions after sun exposure.

What to do: Discuss with your health care provider. (1)

Serotonin-related side effects from combining St. John's wort with certain antidepressants or other drugs that affect serotonin

What to notice: Increased serotonin-related side effects, which can be serious. Symptoms occur within minutes to hours, and may include agitation, diarrhea, fast heartbeat, high blood pressure, hallucinations, increased body temperature, and more.

What to do: This combination is potentially life-threatening. Seek prompt medical assessment. (1) (2)

Worsening of psychotic symptoms

What to notice: Case reports describe dangerous side effects of St. John's wort, such as worsening of psychotic symptoms in people with bipolar disorder or schizophrenia.

What to do: Seek prompt medical assessment. (2)

Colic, drowsiness, and lethargy in a breastfed infant

What to notice: Breastfeeding infants of mothers who take St. John's wort can experience colic, drowsiness, and lethargy.

What to do: Seek medical advice about breastfeeding and St. John's wort. (1)

Serious warnings

Dangerous interactions with a wide range of medicines — emergency

Symptoms: St. John's wort can weaken the effects of many medicines, including crucially important medicines, and interactions can weaken the effects of life-saving medicines or cause dangerous side effects. Examples given include some antidepressants (including amitriptyline and bupropion), birth control pills, cyclosporine, some drugs used to prevent seizures (including phenytoin and carbamazepine), some heart medications (including digoxin and ivabradine), some HIV drugs (including indinavir and nevirapine), some cancer medications (including irinotecan, imatinib, and docetaxel), warfarin, and certain statins including simvastatin. Additional examples listed include oxycodone and indinavir.

Action: It has been clearly shown that St. John's wort can interact in dangerous, sometimes life-threatening ways with a variety of medicines. If you take any type of medicine, talk with your health care provider before using St. John's wort, and tell your providers about everything you take. (1) (2)

Potentially life-threatening increase in serotonin — emergency

Symptoms: Combining St. John's wort and certain antidepressants can lead to a potentially life-threatening increase in your body's levels of serotonin. Symptoms occur within minutes to hours, and may include agitation, diarrhea, fast heartbeat, high blood pressure, hallucinations, increased body temperature, and more.

Action: Seek emergency medical care for these symptoms. Talk with your health care provider before combining St. John's wort with any medicine. (2)

Depression and suicide risk — urgent

Symptoms: Depression can be a serious illness and lead to an increased risk of suicide. For some people, depression can increase the risk of suicide. Symptoms of depression vary but can include feeling sad or anxious often or all the time, not wanting to do activities that used to be fun, feeling irritable, easily frustrated, or restless, problems with sleep and feeling tired, eating more or less than usual or having no appetite, pain that doesn't improve with treatment, trouble concentrating, remembering details, or making decisions, feeling guilty, worthless, or helpless, and thinking about suicide or hurting yourself.

Action: Depression can become severe if you don't get effective, professional help. Do not use St. John's wort to replace conventional care or to postpone seeing your health care provider. If you or someone you know may have depression, talk to a health care provider. (2)

Interactions

Medicine or test	Effect	Action
Antidepressants	St. John's wort can weaken the effects of many medicines, including some antidepressants such as amitriptyline and bupropion. Combining St. John's wort with certain antidepressants can lead to a potentially life-threatening increase in the body's levels of serotonin.	Talk with your health care provider before using St. John's wort if you take any medicine. (1) (2)
Birth control pills	St. John's wort can weaken the effects of birth control pills.	Talk with your health care provider before using St. John's wort. (1) (2)
Cyclosporine	St. John's wort can weaken the effects of cyclosporine, which prevents the body from rejecting transplanted organs.	Talk with your health care provider before using St. John's wort. (1) (2)
Drugs used to prevent seizures	St. John's wort can weaken the effects of some drugs used to prevent seizures, including phenytoin and carbamazepine.	Talk with your health care provider before using St. John's wort. (1)
Heart medications	St. John's wort can weaken the effects of some heart medications, including digoxin and ivabradine; digoxin is also listed as a medicine whose effects St. John's wort can weaken in the depression source.	Talk with your health care provider before using St. John's wort. (1) (2)
HIV drugs	St. John's wort can weaken the effects of some HIV drugs, including indinavir and nevirapine; indinavir is also listed in the depression source.	Talk with your health care provider before using St. John's wort. (1) (2)
Cancer medications	St. John's wort can weaken the effects of some cancer medications, including irinotecan, imatinib, and docetaxel; irinotecan is also listed in the depression source.	Talk with your health care provider before using St. John's wort. (1) (2)
Warfarin	St. John's wort can weaken the effects of warfarin, an anticoagulant (blood thinner).	Talk with your health care provider before using St. John's wort. (1) (2)
Certain statins	St. John's wort can weaken the effects of certain statins, including simvastatin.	Talk with your health care provider before using St. John's wort. (1)
Oxycodone	St. John's wort can weaken the effects of oxycodone, a pain medicine.	Talk with your health care provider before using St. John's wort. (2)
Other drugs that affect serotonin	Taking St. John's wort with certain antidepressants or other drugs that affect serotonin (a substance produced by some nerve cells) may lead to increased serotonin-related side effects, which can be serious.	Talk with your health care provider before using St. John's wort. (1)

Pregnancy, breastfeeding, kidney/liver function, age

Pregnancy

It may be unsafe to use St. John's wort during pregnancy because it may increase the risk of birth defects. We have little safety information on St. John's wort for pregnant women. Talk with health care providers if you're pregnant or considering a dietary supplement. (1) (2)

Breastfeeding

Breastfeeding infants of mothers who take St. John's wort can experience colic, drowsiness, and lethargy. Talk with health care providers if you're nursing. (1)

Children

Many dietary supplements haven't been tested in children, and we have little safety information on St. John's wort for children. Talk with health care providers if you are considering giving a dietary supplement to a child. (2)

People taking any kind of medicine

If you take any type of medicine, talk with your health care provider before using St. John's wort or other herbal products; some herbs and medicines interact in harmful ways. (1)

Monitoring

Before starting

Talk with your health care provider before using St. John's wort if you take any type of medicine.
Tell your health care providers about any complementary health approaches you use.
If you are thinking about using an herbal medicine, first get information on it from reliable sources.
If you or someone you know may have depression, consult a health care provider.

During treatment

Report new or worsening symptoms, especially serotonin-related symptoms, to a health care provider promptly.
Discuss any side effects, such as upset stomach, dry mouth, headache, fatigue, dizziness, confusion, sexual dysfunction, or sensitivity to sunlight, with your health care provider.
Note that these sources do not establish a monitoring plan, laboratory tests, or dose adjustments for St. John's wort.

(1) (2) (3)

Storage

Not established by the sources on this page. Follow the storage directions on the specific product label and ask your pharmacist if these are unclear.

Professional information

Clinician-facing context only. This page is compiled from US government sources (NIH NCCIH and NLM MedlinePlus) and does not provide prescribing, dosing, or monitoring guidance. Dietary supplements are not approved by the US FDA for safety or effectiveness before sale.

All regions

Indication: Any St. John's wort use

Dose summary: No dose is provided by these sources. Disclosure: no dose, schedule, or duration of use is established by the research notes for this page.

Renal context: Not established by the sources on this page. (1) (2)

Mechanism of action

Hepatic guidance

Not established by the sources on this page.

Overdose note

Dietary supplements can cause medical problems if you use them incorrectly or in large amounts. No specific overdose amounts or management are provided by these sources. (1) (2)

Frequently asked questions

Does St. John's wort work for depression?

The results of studies are mixed, and St. John's wort isn't consistently effective for depression. Many studies indicate that it may be helpful for mild or moderate depression, appearing more effective than placebo and as effective as standard antidepressants for mild or moderate depression, but it's uncertain whether this is true for severe depression or for time periods longer than 12 weeks. Do not use it to replace conventional care or to postpone seeing your health care provider. (1) (2)

Is St. John's wort safe?

For most adults who are not taking any kind of medicine, St. John's wort appears to be safe when used for up to 12 weeks, and some studies indicate that it can be used safely for a year or more. If taken orally in large doses or applied to the skin, it might cause severe skin reactions after sun exposure. It may be unsafe during pregnancy, and breastfeeding infants of mothers who take it can experience colic, drowsiness, and lethargy. (1)

Can St. John's wort interact with my medicines?

Yes. It has been clearly shown that St. John's wort can interact in dangerous, sometimes life-threatening ways with a variety of medicines, and it can weaken the effects of many medicines, including crucially important ones such as some antidepressants, birth control pills, cyclosporine, some seizure drugs, some heart medications, some HIV drugs, some cancer medications, warfarin, and certain statins. Combining it with certain antidepressants or other drugs that affect serotonin may lead to serious serotonin-related side effects. Talk with your health care provider before using it. (1) (2)

Is St. John's wort regulated like a medicine in the US?

No. Many herbal products intended for oral use are marketed as dietary supplements, and unlike drugs, dietary supplements are not approved by the U.S. Food and Drug Administration (FDA) before they are sold to the public. Manufacturers and distributors are responsible for evaluating the safety and labeling of their products before marketing. When public health concerns arise about the safety of a dietary supplement or an ingredient including an herb, the FDA can take action to protect the public. (1) (3)

Are 'natural' products always safe?

Not necessarily. Many people believe that products labeled "natural" are always safe and good for them, but this is not necessarily true. Herbal medicines do not have to go through the testing that drugs do, some herbs such as comfrey and ephedra can cause serious harm, and some herbs can interact with prescription or over-the-counter medicines. (3)

What is the mechanism of action of St. John's wort?

What is the generic name of St. John's wort?

The generic name is St. John's wort. (1) (2) (3)

What class of drug is St. John's wort?

St. John's wort is classed as: Herbal product marketed as a dietary supplement in the United States. (1) (2) (3)

References

St. John's Wort: Usefulness and SafetyNational Center for Complementary and Integrative Health (NCCIH), U.S. National Institutes of Health · United States · dated 2025-05 (Last Updated May 2025) · accessed 2026-10-13 · source 1
St. John's Wort and Depression: In DepthNational Center for Complementary and Integrative Health (NCCIH), U.S. National Institutes of Health · United States · dated 2017-12 (Last Updated December 2017) · accessed 2026-10-13 · source 2
Herbal MedicineMedlinePlus, U.S. National Library of Medicine · United States · accessed 2026-10-13 · source 3

Brand names by country

Single-ingredient St. John's wort names are shown separately by country. Product availability, strengths, and supply rules can change; combination products are not included here.

Priority countries

United States

Hypericum 3Xliquid · 3 [hp_X]/mL · uriel pharmacy, incregulator source
BM Hypericumglobule · 200 [hp_C]000mg · bm private limitedregulator source

View brands in additional countries.