Moderate Traumatic Brain Injury (TBI)

The goal of this pilot clinical trial is to learn whether memantine can be given safely and successfully to adults in hospital with a mild or moderate traumatic brain injury (TBI). Memantine is approved to treat Alzheimer's disease, but it is not approved to treat TBI. The study will also test whether brain scans and other assessments are suitable for a larger trial. TBI can damage the blood-brain barrier. This protective lining controls what can pass from the bloodstream into the brain. Researchers can measure this damage with a specialized magnetic resonance imaging (MRI) scan using contrast dye. The main questions are: * Can participants start memantine soon after their injury and take it for three months? * How safe and tolerable are daily memantine doses of 20 mg and 30 mg? * Can MRI scans measure changes in the blood-brain barrier from the start of the study to three months? * Can researchers complete the study visits and collect enough information to plan a larger trial? The study will include 45 adults admitted to the Halifax Infirmary in Nova Scotia, Canada, with a non-penetrating mild or moderate TBI. A computer will assign each participant by chance to one of three groups. One group will receive 20 mg of memantine per day. Another group will receive 30 mg per day. The third group will receive usual care without memantine. The memantine dose will increase gradually based on how well each participant tolerates it. Participants will: * Receive usual care, with or without memantine for three months; * Have specialized MRI scans near the start of the study and at three months; * Have recordings of brain activity near the start, at three months, and at six months; and * Complete tests and questionnaires about symptoms, memory, attention, mood, daily function, disability, and quality of life. Researchers will compare the groups to look for differences in blood-brain barrier changes, side effects, and recovery measures. Because this is a small pilot study, it is not designed to prove that memantine improves recovery. Its results will instead help researchers choose a dose, assess safety of drug delivery, and design a larger trial.

The long-term goal of the clinical trial is to develop effective, safe, and easily administered life-saving treatments for patients with moderate to severe traumatic brain injury (TBI). Patients with moderate to severe TBI will randomly receive either: 1. Standard of care treatment and normal saline 2. Standard of care treatment and one dose of valproic acid (VPA) at a lower dose or a higher dose

Memantine has shown promise in mitigating secondary brain injury in previous studies. One study demonstrated that early memantine administration in moderate TBI patients resulted in lower serum neuron-specific enolase levels and improved Glasgow Coma Scale scores. However, other trials investigating memantine's impact on long-term cognitive function in TBI patients have yielded mixed results. There is a need for well-controlled studies to determine the efficacy of memantine in improving neurological and cognitive outcomes in patients with TBI.