Ten patients presenting agitation and anger outbursts at various stages following a severe closed head injury, were treated in a prospective open trial with carbamazepine, with doses ranging from 400 to 800 mg per day, during 8 weeks. Group analysis demonstrated a statistically significant improvement of a score made up from six target items from the neurobehavioural rating scale. Improvement mainly concerned irritability and disinhibition. A statistically significant improvement was also found with the Agitated Behaviour Scale. Social functioning, as assessed by family or staff ratings of the Katz Adjustment Scale, also significantly improved. No modification of global cognitive functioning was found with the Mini Mental Status Examination. Individual analysis demonstrated that the beneficial effect was important in five cases, moderate in three patients and negligible in two cases. It is concluded that carbamazepine might help to reduce agitated behaviour in brain-injured patients. However, response to treatment demonstrated an important inter-individual variability.