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St. John's wort

Pronunciation: SAINT JOHN'S WORT

What is the most important information I should know about St. John's wort?

Multum nosun

Avoid prolonged exposure to sunlight. St. John's wort may increase the sensitivity of your skin to the sun. Use a sunscreen and wear protective clothing when exposure to the sun is unavoidable.

St. John's wort has not been evaluated by the FDA for safety, effectiveness, or purity. All potential risks and/or advantages of St. John's wort may not be known. Additionally, there are no regulated manufacturing standards in place for these compounds. There have been instances where herbal/health supplements have been sold which were contaminated with toxic metals or other drugs. Herbal/health supplements should be purchased from a reliable source to minimize the risk of contamination.

What is St. John's wort?

The use of St. John's wort in cultural and traditional settings may differ from concepts accepted by current Western medicine. When considering the use of herbal supplements, consultation with a primary health care professional is advisable. Additionally, consultation with a practitioner trained in the uses of herbal/health supplements may be beneficial, and coordination of treatment among all health care providers involved may be advantageous.

St. John's wort is also known as Hypericum perforatum, klamath weed, John's wort, amber touch-and-heal, goatweed, rosin rose, and milleperituis.

St. John's wort has been used in the treatment of anxiety, mild to moderate depression, stomach upset, insomnia, fluid retention, and hemorrhoids. St. John's wort has also been used topically in the treatment of nerve and muscle pain, skin inflammation, skin wounds, and burns.

St. John's wort has not been evaluated by the FDA for safety, effectiveness, or purity. All potential risks and/or advantages of St. John's wort may not be known. Additionally, there are no regulated manufacturing standards in place for these compounds. There have been instances where herbal/health supplements have been sold which were contaminated with toxic metals or other drugs. Herbal/health supplements should be purchased from a reliable source to minimize the risk of contamination.

St. John's wort may also have uses other than those listed in this medication guide.

Who should not take St. John's wort?

Before taking St. John's wort, talk to your doctor, pharmacist, or health care professional if you have any other medical conditions, allergies (especially to plants), or if you take other medicines or other herbal/health supplements. St. John's wort may not be recommended in some situations.

Multum nopreg

Do not take St. John's wort without first talking to your doctor if you are pregnant or could become pregnant. It is not known whether St. John's wort will be harmful to an unborn baby.

Multum nobrfeed

Do not take St. John's wort without first talking to your doctor if you are breast-feeding a baby. It is also not known whether St. John's wort will be harmful to a nursing infant.

There is no information available regarding the use of St. John's wort by children. Do not give any herbal/health supplement to a child without first talking to the child's doctor.

How should I take St. John's wort?

The use of St. John's wort in cultural and traditional settings may differ from concepts accepted by current Western medicine. When considering the use of herbal supplements, consultation with a primary health care professional is advisable. Additionally, consultation with a practitioner trained in the uses of herbal/health supplements may be beneficial and coordination of treatment among all health care providers involved may be advantageous.

If you choose to take St. John's wort, use it as directed on the package or as directed by your doctor, pharmacist, or other health care provider.

Standardized extracts, tinctures, and solid formulations of herbal/health supplements may provide a more reliable dose of the product.

Multum water

Take the pill forms of St. John's wort with a full glass of water.

Some forms of St. John's wort can be brewed to form a tea for drinking.

Multum external

Use the topical forms of St. John's wort externally only.

Multum donot

Do not take more of this medication than is recommended. Too much medicine could be dangerous.

Multum donot

Do not use different formulations (e.g., tablets, topical formulations, teas, tinctures, and others) of St. John's wort at the same time, unless specifically directed to do so by a health care professional. Using different formulations together increases the risk of an overdose of St. John's wort.

Store St. John's wort as directed on the package. In general, St. John's wort should be protected from light and moisture and stored in a sealed container.

What happens if I miss a dose?

No information is available regarding a missed dose of St. John's wort. Consult your doctor, pharmacist, or health care professional if you require further information.

What happens if I overdose?

Multum emt

Seek emergency medical attention.

Symptoms of a St. John's wort overdose are not known.

What should I avoid while taking St. John's wort?

Multum nosun

Avoid prolonged exposure to sunlight. St. John's wort may increase the sensitivity of your skin to the sun. Use a sunscreen and wear protective clothing when exposure to the sun is unavoidable.

St. John's wort may increase the effects of other drugs that cause drowsiness or dizziness, including antidepressants, alcohol, sedatives (used to treat insomnia), pain relievers, anxiety medicines, muscle relaxants, other antihistamines, and topical medications that contain an antihistamine (e.g., anti-itch creams). Tell your doctor about all medicines that you are taking, and do not take any medicine without first talking to your doctor.

What are the possible side effects of St. John's wort?

Multum emt

Although uncommon, allergic reactions to St. John's wort have been reported. Stop taking St. John's wort and seek emergency medical attention if you experience symptoms of a serious allergic reaction including difficulty breathing; closing of your throat; swelling of your lips, tongue, or face; or hives.

Other less serious side effects have been more frequently reported. Talk to your doctor or pharmacist if you experience

  • increased skin sensitivity to sunlight,
  • a rash,
  • a feeling of fullness in your stomach, or
  • constipation.

Side effects other than those listed here may also occur. Talk to your doctor, pharmacist, or health care provider about any side effect that seems unusual or that is especially bothersome. You may report side effects to FDA at 1-800-FDA-1088.

What other drugs will affect St. John's wort?

Multum donot

St. John's wort may interact with many other medicines, possibly increasing side effects or resulting in decreased therapeutic effects. Do not take St. John's wort without first talking to your doctor if you are taking any other medicines, especially any of the following:

  • a monoamine oxidase inhibitor such as tranylcypromine (Nardil), phenelzine (Parnate), or isocarboxazid (Marplan);
  • a selective serotonin reuptake inhibitor such as citalopram (Celexa), fluvoxamine (Luvox), fluoxetine (Prozac), paroxetine (Paxil), or sertraline (Zoloft);
  • a migraine medicine such as almotriptan (Axert), frovatriptan (Frova), eletriptan (Relpax), naratriptan (Amerge), sumatriptan (Imitrex), or zolmitriptan (Zomig);
  • a tricyclic antidepressant such as amitriptyline (Elavil), amoxapine (Asendin), clomipramine (Anafranil), desipramine (Norpramin), doxepin (Sinequan), imipramine (Tofranil), nortriptyline (Pamelor), protriptyline (Vivactil), or trimipramine (Surmontil);
  • furazolidone (Furoxone);
  • linezolid (Zyvox);
  • procarbazine (Matulane);
  • selegiline (Eldepryl);
  • bupropion (Wellbutrin, Zyban);
  • trazodone (Desyrel) or nefazodone (Serzone);
  • venlafaxine (Effexor);
  • mirtazapine (Remeron);
  • sodium oxybate (Xyrem);
  • levomethadyl acetate (Orlaam);
  • cyclosporine (Sandimmune, Neoral, Gengraf);
  • an HIV/AIDS protease inhibitor such as indinavir (Crixivan), lopinavir-ritonavir (Kaletra), amprenavir (Agenerase), nelfinavir (Viracept), ritonavir (Norvir), or saquinavir (Fortovase, Invirase); or
  • an HIV/AIDS non-nucleoside reverse transcriptase inhibitor such as delavirdine (Rescriptor), efavirenz (Sustiva), or nevirapine (Viramune).

You may not be able to take St. John's wort, or you may require a dosage adjustment or special monitoring during treatment if you are taking any of the medicines listed above.

St. John's wort may increase the effects of other drugs that cause drowsiness or dizziness, including antidepressants, alcohol, sedatives (used to treat insomnia), pain relievers, anxiety medicines, muscle relaxants, other antihistamines, and topical medications that contain an antihistamine (e.g., anti-itch creams). Tell your doctor about all medicines that you are taking, and do not take any medicine without first talking to your doctor.

Drugs other than those listed here may also interact with St. John's wort or affect your condition. Talk to your doctor and pharmacist before taking any prescription or over-the-counter medicines or herbal/health supplements.

Where can I get more information?

Your doctor, pharmacist, or health care provider may have more information about St. John's wort.


Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.

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