Biomaterial Database

Xanthine interference with dipyridamole-thallium-201 myocardial imaging. 1995

E J Stanek, and G P Melko, and S L Charland

Department of Pharmacy Practice and Pharmacy Administration, Philadelphia College of Pharmacy and Science, PA, USA.

Both theophylline and caffeine have been shown to antagonize adenosine and are associated with false-negative test results with dipyridamole-T1-201 imaging. This has led to recommendations for theophylline and caffeine abstinence for at least 24 hours prior to dipyridamole-T1-201 imaging. Because pentoxifylline and its metabolites are structurally similar to theophylline and caffeine, and pentoxifylline has adenosine antagonistic properties, one might presume that pentoxifylline may also attenuate the diagnostic yield of dipyridamole-T1-201 imaging. To the best of our knowledge, the pharmacodynamic interaction between pentoxifylline and dipyridamole and its effects on dipyridamole-T1-201 imaging in patients have never been studied adequately. However, a single study in 7 dogs does suggest that there may be no significant interaction. In addition, we must also consider the nonacute nature of the clinical use of pentoxifylline in peripheral vascular disease and the critical need for accurate dipyridamole-T1-201 imaging results and the cost associated with this procedure. Until such information is available in humans, it would be prudent to discontinue pentoxifylline, in addition to caffeinated foods, caffeine-containing drug products, and theophylline, at least 24 hours prior to dipyridamole-T1-201 imaging.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D010431	Pentoxifylline	A METHYLXANTHINE derivative that inhibits phosphodiesterase and affects blood rheology. It improves blood flow by increasing erythrocyte and leukocyte flexibility. It also inhibits platelet aggregation. Pentoxifylline modulates immunologic activity by stimulating cytokine production.	Agapurin,BL-191,Oxpentifylline,Pentoxil,Torental,Trental,BL 191,BL191
D011877	Radionuclide Imaging	The production of an image obtained by cameras that detect the radioactive emissions of an injected radionuclide as it has distributed differentially throughout tissues in the body. The image obtained from a moving detector is called a scan, while the image obtained from a stationary camera device is called a scintiphotograph.	Gamma Camera Imaging,Radioisotope Scanning,Scanning, Radioisotope,Scintigraphy,Scintiphotography,Imaging, Gamma Camera,Imaging, Radionuclide
D002110	Caffeine	A methylxanthine naturally occurring in some beverages and also used as a pharmacological agent. Caffeine's most notable pharmacological effect is as a central nervous system stimulant, increasing alertness and producing agitation. It also relaxes SMOOTH MUSCLE, stimulates CARDIAC MUSCLE, stimulates DIURESIS, and appears to be useful in the treatment of some types of headache. Several cellular actions of caffeine have been observed, but it is not entirely clear how each contributes to its pharmacological profile. Among the most important are inhibition of cyclic nucleotide PHOSPHODIESTERASES, antagonism of ADENOSINE RECEPTORS, and modulation of intracellular calcium handling.	1,3,7-Trimethylxanthine,Caffedrine,Coffeinum N,Coffeinum Purrum,Dexitac,Durvitan,No Doz,Percoffedrinol N,Percutaféine,Quick-Pep,Vivarin,Quick Pep,QuickPep
D003327	Coronary Disease	An imbalance between myocardial functional requirements and the capacity of the CORONARY VESSELS to supply sufficient blood flow. It is a form of MYOCARDIAL ISCHEMIA (insufficient blood supply to the heart muscle) caused by a decreased capacity of the coronary vessels.	Coronary Heart Disease,Coronary Diseases,Coronary Heart Diseases,Disease, Coronary,Disease, Coronary Heart,Diseases, Coronary,Diseases, Coronary Heart,Heart Disease, Coronary,Heart Diseases, Coronary
D004176	Dipyridamole	A phosphodiesterase inhibitor that blocks uptake and metabolism of adenosine by erythrocytes and vascular endothelial cells. Dipyridamole also potentiates the antiaggregating action of prostacyclin. (From AMA Drug Evaluations Annual, 1994, p752)	Antistenocardin,Apo-Dipyridamole,Cerebrovase,Cléridium,Curantil,Curantyl,Dipyramidole,Kurantil,Miosen,Novo-Dipiradol,Persantin,Persantine,Apo Dipyridamole,Novo Dipiradol
D004285	Dogs	The domestic dog, Canis familiaris, comprising about 400 breeds, of the carnivore family CANIDAE. They are worldwide in distribution and live in association with people. (Walker's Mammals of the World, 5th ed, p1065)	Canis familiaris,Dog
D005188	False Negative Reactions	Negative test results in subjects who possess the attribute for which the test is conducted. The labeling of diseased persons as healthy when screening in the detection of disease. (Last, A Dictionary of Epidemiology, 2d ed)	False Negative Reaction,Reaction, False Negative,Reactions, False Negative
D006321	Heart	The hollow, muscular organ that maintains the circulation of the blood.	Hearts
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man