Do some medications interact with grapefruit juice?
Some prescription medications may indeed interact with grapefruit juice. Various chemical processes help break down medications within the body, and studies have found that grapefruit juice and whole grapefruit block a specific enzyme in the liver and the small intestines - interacting with the way medications interact with the body. Only medications that are metabolized by this enzyme will be affected by grapefruit juice. The result of the interaction is higher-than-normal blood levels of the medication and potential adverse effects. The increases in blood levels of the medication may continue 24 hours after consuming grapefruit juice.
Medications affected by this interaction include certain calcium channel blockers (for example, nifedipine), benzodiazepines (including alprazolam and diazepam), some cholesterol-lowering medications in the statin family (such as lovastatin and simvastatin), and medications used to suppress the immune system (for example, cyclosporine).
Note that tangelos and Seville oranges and their juice may have a similar effect as grapefruit.
Check with your doctor or pharmacist to find out if the prescription drug you take may interact with grapefruit juice, or to find out if a non-interacting medication is available to treat your condition.
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