Much of the damage caused by a thrombotic or embolic stroke occurs in the first few hours. The primary areas of research have focused on the development of new clot-dissolving drugs and medications that make the brain more resistant to stroke (neuroprotective agents).

Drugs that dissolve clots are known as thrombolytic agents. Clinical studies suggest that if given within the first few hours after stroke onset, these drugs may dramatically minimize stroke damage.

Thrombolytic Agents (tissue plasminogen activator [tPA]), widely used to dissolve clots that cause heart attacks, are also effective for dissolving artery-blocking clots in the brain during the critical early stages of stroke. Early administration of tPA after a stroke can reduce neurological damage significantly.