St. John's Wort (hypericin) inhibits monoamine oxidase, a chemical associated with depression. In other words, hypericin is a
"MAO inhibitor".
MAO inhibitors were commonly prescribed by conventional medical doctors in the past to treat depression. However, in recent years, other types of anti-depressants have become much more popular because they have far fewer side effects and drug interactions.
MAO inhibitors should not be used when a person eats substances containing the amino acid tyramine. If this caution is not followed, convulsions, extremely high fever and death may occur. MAO inhibitors also react with many commonly prescribed medications, and such drug interactions can cause very serious problems. So when your doctor asks what "medicines" you are taking, always also tell him/her about any over the counter preparations, and BOTANICAL substances you are using!
If you plan on using Saint John's Wort, you need to be aware that the following foods contain either tyramine or bacteria with
enzymes that can convert tyrosine to tyramine: Alcoholic beverages, products made with yeast, aged cheese, sour cream, liver,
canned meats, salami, sausage, pickled herring, eggplant, and soy sauce.
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