Trademarked as Persantine.
Inhibits blood clot formation[ when given chronically and causes blood vessel dilation when given at high doses over a short time.
Pregnancy category B.
Routes of administration by mouth, and IV.
Protein binding ~99%
Metabolismis by liver glucuronidation.
Biological half-life α phase: 40 min,
β phase: 10 hours
Excretion biliary (95%), and urine is negligible.
It inhibits the phosphodiesterase enzymes that normally break down cAMP, thereby increasing cellular cAMP levels and blocking the platelet aggregation response to ADP) and/or cGMP.
It inhibits the cellular reuptake of adenosine into platelets, red blood cells, and endothelial cells leading to increased extracellular concentrations of adenosine.
Dipyridamole is used to dilate blood vessels in peripheral arterial disease and coronary artery disease, and lowers pulmonary hypertension without significant drop of systemic blood pressure.
It inhibits formation of pro-inflammatory cytokines (MCP-1, MMP-9) in vitro and results in reduction of hsCRP in patients.
It inhibits proliferation of smooth muscle cells and increases patency of synthetic arteriovenous hemodialysis grafts.
Increases the release of t-PA from brain microvascular endothelial cells, and reduces thrombogenicity of the subendothelial matrix.
Increases myocardial perfusion and left ventricular function in patients with ischemic cardiomyopathy.
It results in a reduction of the number of thrombin receptors on platelets in stroke patients.
cAMP impairs platelet aggregation and also causes arteriolar smooth muscle relaxation.
It can be used for myocardial stress testing as an alternative to exercise-induced stress methods.
A combination of dipyridamole and aspirin is approved for the secondary prevention of stroke and has a bleeding risk equal to that of aspirin use alone.
Dipyridamole absorption is pH-dependent and concomitant treatment with gastric acid suppressors, such as a proton pump inhibitor, inhibits its absorption, while modified release preparations are buffered and absorption is not affected.
May reduce the risk of further vascular events in patients presenting after cerebral ischemia.
Vasodilation occurs in healthy arteries, whereas stenosed arteries remain narrowed, and can create a steal phenomenon where the coronary blood supply will increase to the dilated healthy vessels compared to the stenosed arteries which can then be detected by manifesting chest pain, electrocardiogram and echocardiography changes when it causes ischemia.
Flow heterogeneity can be detected with gamma cameras and SPECT using nuclear imaging agents such as Thallium-201, Tc99m-Tetrofosmin and Tc99m-Sestamibi.
Dipyridamole overdose can be treated with aminophylline, which reverses its dilating effect on the blood vessels.
Dipyridamole overdose may require a vasopressor drug, and gastric
Symptomatic treatment is recommended, possibly including a vasopressor drug., and gastric lavage should be considered.