Medication or drug therapy is the most common treatment for stroke. The most popular classes of drugs used to prevent or treat stroke are antithrombotics (antiplatelet agents and anticoagulants), thrombolytics, and neuroprotective agents.

Antithrombotics prevent the formation of blood clots that can become lodged in a cerebral artery and cause strokes. Antiplatelet drugs prevent clotting by decreasing the activity of platelets, blood cells that contribute to the clotting property of blood. These drugs reduce the risk of blood-clot formation, thus reducing the risk of ischemic stroke. In the context of stroke, physicians prescribe antiplatelet drugs mainly for prevention. The most widely known and used antiplatelet drug is aspirin. Other antiplatelet drugs include clopidogrel and ticlopidine. The National Institute for Neurological Disorders and Stroke (NINDS) sponsors a wide range of clinical trials to determine the effectiveness of antiplatelet drugs for stroke prevention.

Anticoagulants reduce stroke risk by reducing the clotting property of the blood. The most commonly used anticoagulants include warfarin (also known as Coumadin® ) and heparin. The NINDS has sponsored several trials to test the efficacy of anticoagulants versus antiplatelet drugs. The Stroke Prevention in Atrial Fibrillation (SPAF) trial found that, although aspirin is an effective therapy for the prevention of a second stroke in most patients with atrial fibrillation, some patients with additional risk factors do better on warfarin therapy. Another study, the Trial of Org 10127 in Acute Stroke Treatment (TOAST), tested the effectiveness of low-molecular weight heparin (Org 10172) in stroke prevention. TOAST showed that heparin anticoagulants are not generally effective in preventing recurrent stroke or improving outcome.

Thrombolytic agents are used to treat an ongoing, acute ischemic stroke caused by an artery blockage. These drugs halt the stroke by dissolving the blood clot that is blocking blood flow to the brain. Recombinant tissue plasminogen activator (rt-PA) is a genetically engineered form of t-PA, a thombolytic substance made naturally by the body. It can be effective if given intravenously within 3 hours of stroke symptom onset, but it should be used only after a physician has confirmed that the patient has suffered an ischemic stroke. Thrombolytic agents can increase bleeding and therefore must be used only after careful patient screening. The NINDS rt-PA Stroke Study showed the efficacy of t-PA and in 1996 led to the first FDA-approved treatment for acute ischemic stroke. Other thrombolytics are currently being tested in clinical trials.

Neuroprotectants are medications that protect the brain from secondary injury caused by stroke. Although only a few neuroprotectants are FDA-approved for use at this time, many are in clinical trials. There are several different classes of neuroprotectants that show promise for future therapy, including calcium antagonists, glutamate antagonists, opiate antagonists, antioxidants, apoptosis inhibitors, and many others. One of the calcium antagonists, nimodipine, also called a calcium channel blocker, has been shown to decrease the risk of the neurological damage that results from subarachnoid hemorrhage. Calcium channel blockers, such as nimodipine, act by reducing the risk of cerebral vasospasm, a dangerous side effect of subarachnoid hemorrhage in which the blood vessels in the subarachnoid space constrict erratically, cutting off blood flow.

Return to Know Stroke Home Page

Return to St. Joseph Hospital Home Page