Anticoagulants.Anticoagulants thin blood and may be useful under certain circumstances.
- Warfarin. The anticoagulant warfarin (Coumadin) may not work as well as aspirin in preventing a second stroke in people who have partial artery blockage in the brain (intracranial stenosis). Warfarin is, however, very important in high-risk patients with atrial fibrillation. It may be useful in other situations, such as patients with patent foramen ovale (PFO), those whose stroke followed a heart attack, or in high-risk patients who cannot take antiplatelet drugs.
- Heparin. Intravenous heparin, a potent anti-platelet drug, has been used for ischemic stroke since 1941. Although many doctors continue to use it, five out of six major studies have reported no clear protective benefits compared to aspirin with the use of standard heparin or any heparin-like drugs. They also pose a much higher risk for hemorrhagic stroke. Experts now recommend heparins only for preventing thromboembolism in stroke patients at risk for this condition.
- Direct Thrombin Inhibitors (DTIs). Direct thrombin inhibitors are a more recent group of anti-coagulants. The first DTI is hirudin, a natural substance derived from the saliva of leeches. New forms include argatroban (Novastan), bivalirudin (Angiomax), danaparoid (Orgaran), lepirudin (Refludan), desirudin (Revasc), inogatran, and efegatran. Ximelagatran (Exanta) is new oral drug that is showing great promise for protection against stroke in patients with atrial fibrillation while posing a low risk for bleeding.
All anti-clotting drugs carry a risk for bleeding and a slightly increased risk for hemorrhagic stroke.
Other Medications for Preventing a Recurring Stroke
It is important that patients control their high blood pressure and LDL (“bad”) cholesterol levels. Various drugs, such as statins, diuretics, and ACE inhibitors, can manage these conditions. People with diabetes should also maintain tight control of their blood sugar levels.
Drugs for Hemorrhagic Stroke
Calcium Channel Blockers. Early administration of calcium channel blockers, such as nimodipine (Nimotop), can improve functional outcome. One of the most common and serious dangers after a subarachnoid hemorrhagic stroke is spasm of the blood vessels near the ruptured site, which closes off oxygen to the brain. Calcium causes contraction of the smooth muscles of the blood vessels; calcium channel blockers are drugs that relax the blood vessels. The drugs work best if they are administered within 6 hours of the stroke. Calcium channel blockers are not useful for ischemic strokes, although they can be used in combinations with blood pressure lowering drugs to prevent them.
Investigative Therapies to Protect or Restore Nerve Cells after a Stroke
Nerve-Protecting Drugs. More than 50 medications have been studied in clinical trials aimed at slowing or preventing the cascading process that destroys nerve cells after a stroke. Many investigative drugs are targeting the excitatory amino acids, such as glycine and glutamate, which are known to destroy nerve cells after a stroke. Although none to date have proven to have any significant benefits, some are showing promise. They include magnesium sulfate, citicoline, ebselen, piracetam, edaravone, albumin, erythropoietin, and NXY-059.
Investigative Drugs for Nerve Regeneration. Scientists used to think that when cells in the brain were destroyed, new ones could not grow to replace them. Researchers have now observed, however, that nerve regrowth (neurogenesis) can occur in the adult human brain. This exciting discovery opens the way for new drugs that might in the future stimulate nerve growth and repair damage done by many neurologic diseases, including stroke. For example, a 2002 study reported nerve regeneration in animals whose brains were treated with the drug inosine. More research is underway.
Previous Section
