Effectiveness of Amantadine Hydrochloride for Treatment of Severe Traumatic Brain Injury (TBI)

Inclusion Criteria

• Individuals between ages 16 and 65 with traumatic brain injury as defined by the TBI Model System syllabus (i.e., damage to brain tissue caused by an external mechanical force as evidenced by loss of consciousness or post-traumatic amnesia due to brain trauma, skull fracture, or objective neurological findings that can be reasonably attributed to TBI on physical or mental status examination).
• Individuals are at least 4 weeks but less than 16 weeks post-injury and have a Disability Rating Scale (DRS) score at enrollment of 12 or greater, and no consistent command following or functional communication (as defined by the JFK.

Exclusion Criteria

• Women who are pregnant,
• Individuals with missile-type penetrating brain injury,
• Premorbid major CNS/developmental abnormality (e.g., mental retardation, prior significant brain damage, etc.),
• History of more than 1 seizure (clinical or electrographic, but not including epileptiform or other irritative discharges) in the 4 weeks prior to enrollment (individuals with premorbid idiopathic epilepsy are eligible to enroll under two conditions: a) if their pre-injury seizure frequency was less than once/month and they have had no more than 1 seizure/month since injury and b) if a clear provocation was present that would otherwise disqualify a subject, the subject can be enrolled, since these events would not be considered idiopathic),
• Prior exposure to AH post-TBI,
• Unwillingness to discontinue or change confounding psychotropic drugs prior to enrollment, OR
• Allergy or medical contraindication to AH and significant impairment of renal function (as evidenced by a calculated creatinine clearance of < 60 ml/min).