Abstract
Madhu Saraf, Cramond Clinic, North West Adelaide Mental Health Service, and Geoff Schrader, Department of Psychiatry, University of Adelaide, Adelaide, Australia:
We report the case of a seizure occurring in a patient treated for major depression with sertraline. A 34-year-old female with no history of seizures was treated as an inpatient for a major depressive episode with sertraline, titrating the dose up to 150 mg daily with some resolution of symptoms. Computerised tomography (CT) head scan and electroencephalogram (EEG) were unremarkable. On discharge, due to lack of further improvement, the sertraline dose was increased to 200 mg. Subsequently, the patient had a severe tonic clonic seizure. Sertraline was ceased. A repeat EEG showed marked abnormality with multiple paroxysms of sharp/spike and slow wave complexes predominantly over right mid to posterior areas, particularly over the temporal region, and at times bilaterally synchronous. On neurological review, it was considered the EEG findings were consistent with a post-ictal disturbance, rather than the development of epilepsy per se, nonetheless all precautions regarding driving were instituted and she was commenced on carbamazepine 100 mg mane, 200 mg nocte. Subsequently, her depression was treated with citalopram 20 mg mane and she remained seizure free. Seizures are uncommon but serious adverse effects of antidepressants [1]. A significant proportion of antidepressant-related seizures occur in individuals with an identifiable predisposing condition: for example, previous seizures or sedative or alcohol abuse. Seizure risk for most antidepressants increases with dosage. Selective serotonin re-uptake inhibitors (SSRI), including sertraline, generally have low seizure propensity; however, seizure rates at effective dosage have not been described for most SSRIs. Seizures have been reported in association with overdosage of sertraline. Most of the data on proconvulsive effects of anti-depressants come from either work on animal models or from research into the effects of antidepressant overdose. Direct extrapolation from this work to the clinical setting is difficult. For example, in a study of intensity of a seizures in genetically epilepsy-prone rats [2], it was noted that sertraline actually produced a dose-dependent reduction in the intensity of seizures. Our case would seem to highlight the dose dependent nature of seizures related to anti-depressants. Physicians should remain alert to the risk of seizures even with the newer antidepressants.