Common Herb-Rx Drug Interactions

Common Herb–Rx Drug Interactions
Herb	Known Drug Interaction
Aloe	Increases risks associated with cardiac glycosides.
Anise	May interfere with anticoagulants, MAO inhibitors (MAOIs), and hormone therapy.
Brewer’s yeast	MAOIs can cause an increase in BP.
Echinacea	May possibly interfere with immunosuppressant agents.
Eucalyptus	Induction of liver enzymes, which may increase the metabolism of other drugs.
Feverfew	May inhibit platelet activity (avoid use with warfarin or other anticoagulants). May potentiate effects of MAOIs (ginkgo).
Garlic
Ginger
Ginkgo
Ginseng	May potentiate effects of caffeine. May interfere with phenelzine. May inhibit platelet activity (avoid use with warfarin or other anticoagulants).
Goldenseal	May interfere with antacids, sucralfate, H2 antagonists, antihypertensive agents, and anticoagulants.
Hawthorne	May inhibit metabolism of ACE inhibitors and potentiate effect of cardiac glycosides.
Kava-kava	May potentiate or have additive effects of CNS depressants, antiplatelets, and MAOIs.
Ma-huang	Potentiates sympathomimetic effects of antihypertensives, antidepressants, MAOIs.
Oak bark	Inhibits absorption of alkaloids and other alkaline drugs.
Peppermint	May interfere with gastric acid–blocking drugs.
Psyllium	Interferes with absorption of other drugs.
St. John’s wort	May increase risk of adverse reactions of antidepressants. May significantly reduce blood concentrations of indinavir.
Saw palmetto	May interfere with oral contraceptives and hormone therapy.
Valerian	May potentiate sedative effects.
Notes