Severe. These medicines may interact and cause very harmful effects and are usually not taken together. Contact your healthcare professional (e.g. doctor or pharmacist) for more information.
How the interaction occurs:
When these two medicines are taken together, the dipyridamole may have less effect on the blood vessels in your body.
What might happen:
Incorrect test results indicating 'negative' may occur.
What you should do about this interaction:
Before taking this test, tell your doctor about all of the medicines you are taking. Your healthcare professionals (e.g. doctor or pharmacist) may already be aware of this drug interaction and may be monitoring you for it. Do not start, stop, or change the dosage of any medicine before checking with them first.
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2.Smits P, Corstens FH, Aengevaeren WR, Wackers FJ, Thien T. False-negative dipyridamole-thallium-201 myocardial imaging after caffeine infusion. J Nucl Med 1991 Aug;32(8):1538-41.
3.Smits P, Straatman C, Pijpers E, Thien T. Dose-dependent inhibition of the hemodynamic response to dipyridamole by caffeine. Clin Pharmacol Ther 1991 Nov;50(5 Pt 1):529-37.