Psychiatric disorders frequently occur in patients with temporal lobe epilepsy (TLE) (70%). This combination further reduces the quality of life of patients as diagnosis is difficult and therapeutic opportunities are often missed.

The aim of this case study is to show the possible association between TLE and psychiatric semiology and its therapeutic implications.

Presentation of the clinical case of Mr BH who experienced psychosis like symptoms, was finally diagnosed with TLE and put under anti-epileptic drugs.

Mr BH, aged 22, with no family or personal history, was admitted for aggressive behavior, self-harm, pyromania, and depression. Three years prior to onset of psychiatric symptoms, he reports episodes of pulsatile- left-temporal headache followed by hypertonic movements of the neck. Symptoms were intermittently followed by total amnesia or impaired consciousness. The patient explained symptoms by an inner presence that he called “his twin” and to whom he attributed those behaviors contrary to his will. The discovery of bilateral hippocampal atrophy in magnetic resonance imaging with a normal electroencephalography suggested the diagnosis of TLE with post-ictal psychotic disorders. Patient was put initially on diazepam and olanzapine with partial improvement. Association of valproate led to progressive but then complete disappearance of symptoms and so confirmed our diagnosis.

It is often difficult to attach psychiatric symptoms to epilepsy. The diagnosis should be done on a set of clinical, radiological and electrical arguments.

The authors have not supplied their declaration of competing interest.