The aim of the MAST trial is to define best practice in the use of anti-epileptic drugs for patients following a traumatic brain injury through conducting two closely related clinical trials (PROPHYLAXIS and DURATION), which will run in parallel but independently of each other.

• MAST PROPHYLAXIS will compare the clinical effectiveness (absolute difference in the rate of PTS within the first 2 weeks post-TBI) of a 7-day course of phenytoin or levetiracetam, used as seizure prophylaxis, versus no AED for TBI patients.
• MAST DURATION will compare the clinical effectiveness (absolute difference in the rate of late PTS within 24 months post-TBI) of a longer course of phenytoin or levetiracetam (at least 6 months) versus a shorter course (up to 3 months) for TBI patients with early PTS.