A sudden, mechanical head injury that disrupts brain function is termed traumatic brain injury (TBI). Motor vehicle accidents, violence, and falls are the most common causes of TBI. Symptoms such as headache, fatigue, and mood changes can occur across TBI severities. However, in moderate to severe TBI these symptoms may be compounded by progressively worsening headaches, inability to awaken from sleep, agitation, and seizures, among others. Disabilities resulting from TBI depend on the extent of brain damage—cognition deficits and mental health problems are common; in the extreme, severe TBI patients may be in a vegetative state. With no neuroprotective therapies currently available, the treatment goal in TBI is to prevent further brain damage. Surgery may be required for brain hematomas or contusions, and moderate to severe cases require rehabilitation tailored to patients’ specific TBI manifestations.