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St. john's wort Side Effects

It is possible that some side effects of st. john's wort may not have been reported. These can be reported to the FDA here. Always consult a healthcare professional for medical advice.

Applies to st. john's wort: oral capsule, oral tablet

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Although not all side effects are known, St. John's wort is thought to be likely safe when taken by an adult for up to 12 weeks, or by a child age 6-17 for up to 8 weeks. St. John's wort may be unsafe when taken in large doses.

Stop using St. John's wort and call your healthcare provider at once if you have:

  • severe skin rash or irritation;

  • severe sunburn (redness, burning, blistering) after being outdoors; or

  • (if you are also taking an antidepressant or narcotic pain medicine) -- agitation, hallucinations, fever, fast heart rate, overactive reflexes, nausea, vomiting, diarrhea, loss of coordination, fainting.

Common side effects may include:

  • sleep problems (insomnia), strange dreams;

  • feeling anxious, irritable, or restless;

  • dry mouth, upset stomach, diarrhea;

  • skin rash, tingly feeling;

  • headache, dizziness; or

  • tired feeling.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects.

Disclaimer: Every effort has been made to ensure that the information provided is accurate, up-to-date and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This material does not endorse drugs, diagnose patients, or recommend therapy. This information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate safety, effectiveness, or appropriateness for any given patient. Drugs.com does not assume any responsibility for any aspect of healthcare administered with the aid of materials provided. 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 substances you are taking, check with your doctor, nurse, or pharmacist.

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