• Neuropsychiatric Inventory Irritability Domain (frequency and severity) completed by caregiver [ Time Frame: 42 days ] [ Designated as safety issue: No ]
  
• Clinicians Global Impression of Change [ Time Frame: 42 days ] [ Designated as safety issue: No ]
  

• Neuropsychiatric Inventory Aggression Domain (frequency, severity, and caregiver distress) completed by the caregiver [ Time Frame: 42 days ] [ Designated as safety issue: No ]
  
• Neuropsychiatric Inventory Irritability Domain (caregiver distress) completed by the caregiver [ Time Frame: 42 days ] [ Designated as safety issue: No ]
  
• Global Impression of Change [ Time Frame: 42 days ] [ Designated as safety issue: No ]
  
• STAXI-2 by caregiver [ Time Frame: 42 days ] [ Designated as safety issue: No ]
  
• STAXI-2 completed by person with brain injury [ Time Frame: 42 days ] [ Designated as safety issue: No ]
  

It is anticipated that 74 subjects with 74 corresponding subject informants will be recruited at Carolinas Rehabilitation. Subjects will be recruited from the clinic at Carolinas Rehabilitation. Subjects will also be referred by psychiatrists at North Carolina Neuropsychiatry.

Subjects who consent and qualify will be randomized in a 1:1 ratio to Tegretol® or placebo. Stratification to randomization group will occur based on the presence of depression defined by a BDI-II score ≥ 13. Subjects randomized to active drug will be titrated up in dose, as tolerated, over a period of 3 weeks. Starting dose is 200mg twice daily to 200mg three times daily to 200mg, 2 tabs, twice daily. There will be 3 clinic visits. Visits will occur at baseline for consenting and screening, day 28, and day 42. Follow up phone calls will occur each week that the subject is not seen in the clinic until the end of the study. Follow up phone calls will assess for study medication compliance, adverse events and concomitant medication changes. Day 42 ends the period of the Randomized Clinical Trial phase of the study and the subjects will begin the 1 week of taper of Tegretol® at 400mg daily and then stop drug. A safety phone call will be made at day 49.

The following questionnaires will be used as measures of irritability for the subject and the informant: Neuropsychiatric Inventory (NPI), State Trait Anger Expression Inventory (STAXI-2), and Global Impression of Change. The following 3 questionnaires will be dispensed to the subject only: Beck Depression Inventory, Brief Symptom Inventory, and Fatigue Impact Scale. The Investigator will complete the Clinical Global Impression of change at Visits 2 and 3.

History and Physical Exam, hematology, chemistry, including renal and liver function studies will be obtained for safety and tolerability. Serum pregnancy tests will be drawn at screening for females of childbearing potential. Carbamazepine levels will be drawn at visits 2 and 3.