Report on St John’s Wort Side Effects and Usage

St. John’s Wort

Natural health supplements sometimes have unexpected side effects or interactions with medication that can lead to adverse reactions that are sometimes life threatening. The following is a list of cautions that you should be aware of before using St. John’s Wort (Hypericum perforatum). These are referred to as drug/herb interactions.

Warning 1 – Contraindications: Pregnancy and lactation.

Warning 2 – ACE inhibitors: Using St. John’s Wort with ACE inhibitors may lead to severe photosensitivity. Experts recommend avoiding concurrent use.

Warning 3 – Amphetamines: The use of St. John’s Wort with amphetamines may cause serotonin syndrome.

Warning 4 – Antidepressants: The herb/drug interaction between St. John’s Wort and antidepressant may lead to severe photosensitivity. Experts recommend avoiding concurrent use.

Warning 5 – Antiretrovirals: St. John’s Wort reduces the antiretroviral action of the HIV drug, indinavir.

Warning 6 – Oral Contraceptives: When used with birth control pills, may lead to severe photosensitivity. This herb may also reduce the effectiveness of oral contraceptives. Experts recommend avoiding concurrent use.

Warning 7 – Loop Diuretics: Using St. John’s Wort with loop diuretics may lead to severe photosensitivity. Experts recommend avoiding concurrent use.

Warning 8 – Thiazide Diuretics: Using St. John’s Wort with thiazide diuretics may lead to severe photosensitivity. Experts recommend avoiding concurrent use.

Warning 9 – Immunosuppressants: St. John’s Wort has caused the rejection of transplanted hearts when taken with cyclosporine. There is high probability that other immunosuppressants may have the same interaction as well as other transplants.

Warning 10 – MAOIs: St. John’s Wort may increase the action of MAOIs. Experts recommend avoiding concurrent use.

Warning 11 – NSAIDs: When combined with NSAIDs, St. John’s Wort lead to severe photosensitivity. Experts recommend avoiding concurrent use.

Warning 12 – Oral contraceptives: The use of St. John’s Wort with oral contraceptives causes a 13-15% reduction in the dose exposure from norethindrone and ethinyl estradiol contraceptives. This herb increases the risk of breakthrough bleeding, follicle growth and probable ovulation. Experts recommend avoiding concurrent use.

Warning 13 – Paroxetine: St. John’s Wort may increase sedation to a dangerous degree.

Warning 14 – SSRIs: Using St. John’s Wort with SSRIs may lead to coma and/or serotonin syndrome. Experts recommend avoiding concurrent use.

Warning 15 – Trazodone: Using St. John’s Wort with trazodone may cause serotonin syndrome.

Warning 16 – Reyataz (atazanavir): The prescribing information for Reyataz warns against using St. John’s Wort and products containing St. John’s Wort.

Warning 17 – Photosensitivity: If you have fair you may want to avoid exposure to strong sunlight and ultraviolet light while using this herb.

Warning 18 – Soma (carisoprodol): Taking St. John’s Wort while using Soma could decrease the effectiveness of Soma.

Warning 19 – PPIs for GERD: This herb significantly reduces plasma concentrations and effectiveness of Prilosec (omeprazole), Nexium (esomeprazole magnesium) and other PPIs.

Used as a natural health remedy: St. John’s Wort is used internally for the following benefits and conditions:

  • aphrodisiac
  • burn relief
  • moisten dry menopausal skin (tincture)
  • reduced anxiety
  • reduced insomnia
  • symptomatic relief of mild to moderate depression
  • wound healing

Side Effects of St. John’s Wort

The known side effects of using St. John’s Wort include:

  1. Gastrointestinal (GI) upset
  2. Headache
  3. Dry mouth
  4. Confusion
  5. Fatigue
  6. Photosensitization (skin burns quickly in sunlight)

Other side effects may also occur when using St. John’s Wort. (See form below)

As with any herb, a serious allergic reaction is possible. Seek immediate medical attention if you notice any symptoms of a serious allergic reaction. These may include a rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, or trouble breathing.

Alcohol: St. John’s Wort was once thought to increase MAO inhibition and experts recommended avoiding concurrent use. That was based on a theory that has since been proven false.

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