Selected Calcium Channel Antagonists/Grapefruit
This information is generalized and not intended as specific medical advice. Consult your healthcare professional before taking or discontinuing any drug, changing your diet or commencing any course of treatment.
Very important. A change in your diet, medicine, or dosage may be necessary. Promptly consult your doctor or pharmacist.
How the interaction occurs:
When grapefruit or grapefruit juice is taken with you calcium channel blocker medicine, it may increase the amount of the medicine absorbed into your bloodstream.
What might happen:
Your blood levels of this medicine may increase. Increased blood levels may cause a lower-than-desired blood pressure or an undesirable change in heart rate.
What you should do about this interaction:
While you are taking this medicine, do not eat grapefruit or drink grapefruit juice at any time. You may choose an alternative citrus beverage (such as orange juice). In the event that you are instructed by a healthcare professional (e.g., doctor, pharmacist, or dietitian) to eat grapefruit or drink grapefruit juice, you should immediately discuss with your doctor the effects of grapefruit on the blood levels of this medicine.Tell your doctor immediately if symptoms of low blood pressure (such as rapid heartbeat or dizziness) occur. Also report an irregular or unusually slow heartbeat. Contact your healthcare professional for more information.Your healthcare professional may be aware of this interaction and may be monitoring you for it. Do not start, stop, or change your medicine or diet before checking with them first.
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