Grapefruit seed extract is not associated with any side effects, drug interactions, or contraindications. However, a number of medications should not be taken with grapefruit juice itself. These include certain immunosuppressants, cholesterol-lowering drugs, and antihistamines - if in doubt consult a physician. Furthermore, when taken as recommended it does not destroy the ‘healthy’ bacteria that reside in the gastro-intestinal tract.
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