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Know the Science: How Medications and Supplements Can Interact

More About St. John’s Wort

St. John’s wort interacts with many types of drugs. In most instances, it speeds up the processes that change the drug into inactive substances, leading to a decrease in drug levels in your body.

However, St. John’s wort interacts with some drugs in other ways. For example, taking St. John’s wort with certain types of antidepressants can cause harmful side effects.

Some Drugs That Interact With St. John’s Wort
Anti-anxiety drugs
Anticoagulants (blood thinners)
Cancer drugs
Cholesterol-lowering drugs (statins)
Diabetes drugs
Digoxin (digitalis), a drug used to treat heart problems
Drugs that suppress the immune system (used to prevent rejection of transplanted organs)
Drugs used to prevent seizures
Drugs used to treat HIV infection
Fexofenadine (an antihistamine)
Finasteride (a drug used for prostate problems)
Ivabradine (a drug used to treat angina)
Nifedipine and verapamil (used to treat high blood pressure or heart problems)
Omeprazole (an acid reducer used to treat digestive tract problems)
Oral contraceptives (birth control pills)
Talinolol (a beta-blocker used for high blood pressure and heart problems)
Theophylline (an asthma drug)
Voriconazole (a drug used to treat fungal infections)