Dipyridamole is a phosphodiesterase inhibitor also known as Aggrenox and Persantine, used to prevent thromboembolic events post-operation. Routes of administration fall under intravenous or oral administration. Dipyridamole inhibits adenosine deaminase and adenosine transporters leading to the accumulation of adenosine in the extracellular space leading to increased activation of adenosine receptors. This causes the activation of the signalling cascade Gs and increased concentrations of cAMP, which is furthered by dipyridamole inhibiting cAMP phosphodiesterase from breaking down cAMP. Elevated levels of cAMP prevent platelet aggregation and activation, it also inhibits the release of arachidonic acid from membrane phospholipids which strengthens the activity previously mentioned. Dipyridamole is metabolized in the liver to glucuronic acid and excreted out of the body via bile. This drug can cause hypotension, if a patient does experience this it will most likely have a short duration. if the hypotension persists a vasopressor drug can be used to cease this symptom. Due to the anticoagulant and antiplatelet activity herbs and supplements with similar activity should be avoided such as garlic, ginger, bilberry, danshen, piracetam and ginkgo biloba. Xanthines are known to reduce the effectiveness of the drug, care should be taken as it is commonly found in coffees and teas.

Dipyridamole Phosphodiesterase Pathway References