Mild to moderate TBI patients will receive memantine. It will be given either orally or through a nasogastric tube for 7 days, starting on the first day of admission to the hospital and then continued for 3 weeks. The memantine dose in the first 7 days is 30 mg twice daily, while during the remaining 3 weeks the dose is 10 mg twice daily

Mild to moderate TBI patients will be managed by mannitol or hypertonic saline to reduce brain swelling and analgesic for headache such as; acetaminophen.

Memantine will be given either orally or through a nasogastric tube for 7 days, starting on the first day of admission to the hospital and then continued for 3 weeks. The memantine dose in the first 7 days is 30 mg twice daily, while during the remaining 3 weeks the dose is 10 mg twice daily

Score rage: 0 - 30. Normal cognition: 26 - 30, mild cognitive impairment: 18 - 25, moderate cognitive impairment: 10 - 17 and severe cognitive impairment: less than 10.

The differences between study groups in GCS scores over 3 days. The score ranges from 3 (Minimum score = deep coma or death) to 15 (Maximum score = fully awake and oriented). Traumatic brain injury (TBI) is graded as mild, moderate, or severe on the basis of the level of consciousness or Glasgow coma scale (GCS) score after resuscitation. Mild TBI score ranges from 13 to 15, moderate TBI ranges from 9 to 13; while severe TBI ranges from 3 to 8.