Introduction
Stroke is the third-highest cause of death in the U.S. According to statistics from the American Heart Association, strokes account for more than 140,000 deaths a year.
Aggrenox is a drug combination composed of aspirin and extended release dipyridamole, approved by the FDA for use to prevent initial or recurrent strokes. Both drugs have proven effective in the prevention and treatment of stroke. The effects of both drugs combine in Aggrenox.
Mechanisms of a Stroke
Stroke is the result of interruption of blood supply to parts of the central nervous system, chiefly the brain. The interruption can be caused by the rupture of a blood vessel. The blood supply beyond the point of rupture is cut off and there is bleeding into the substance of the brain. This type of stroke is called a hemorrhagic stroke.
The other type of stroke is due to a gradual narrowing of arteries by deposits called thrombi and/or occlusion of the arteries by floating clumps of cells and debris in the blood stream called emboli. These are called vaso-occlusive or thrombo-embolic strokes.
Aggrenox is used in the treatment and prevention of thrombo-embolic strokes.
How Aggrenox Works
Aspirin, one of the two active components of aggrenox, is well known for reducing the frequency of blood clots. Aspirin works on platelets (cells responsible for blood clot formation) to block the production of a substance, thromboxane-A2, that activates the clumping of platelets and the constriction of small arteries. It also reduces the formation of free radicals that increase the stickiness of arterial walls and blood cells.
Dipyridamole interferes with platelet activation in the presence of tissue injury. This reduces the clumping of platelets, thus reducing the likelihood of deposits on the walls and reducing the likelihood of recurrent stroke. It also dilates blood vessels, further discouraging occlusion.
Aggrenox thus combines these mechanisms to block clot formation and further narrowing of blood vessels.
