Levetiracetam Associated Delirium in an Adult Male – A Case Report

Delirium is a potentially life-threatening neuropsychiatric medical emergency, especially in the elderly. Unrecognized or untreated or inappropriately treated delirium may lead to significant morbidity or mortality. Medication-induced delirium is not uncommon in elderly patients with complex medication regimens. Medications are one of the most common precipitating factors for triggering delirium and often one of the most easily correctable. A case of acute onset visual hallucinations associated with levetiracetam addition to an extensive medication regimen in an elderly male with a complex medical and psychiatric history is presented. A Naranjo scale assessment indicated that the acute delirium was in the probable range, in terms of its association with levetiracetam. The patient had multiple risk factors (age, multiple medical comorbidities, history of pre-existing cognitive impairment, treatment with multiple medications known to be risk factors for delirium) predating addition of the levetiracetam, however the addition appeared consistent with the time course of the delirium onset. Levetiracetam prescribing information reports psychotic symptoms in 1% of treated adults versus 0.2% in placebo. New onset psychiatric/behavioral side effects related to levetiracetam were noted in 15.7% of 221 patients in a study of newer AEDs in 2007; greater than those seen with gabapentin, lamotrigine, topiramate, zonisamide, but similar to tiagabine. Anger and aggression were more frequently reported with levetiracetam than other AEDs (49% versus 39% compared to 7% in controls).While delirium is typically multifactorial in etiology, increased medication burden, particularly involving anticholinergics, benzodiazepines, and opiates, among others, is a significant risk factor. With increased use of levetiracetam for neurological indications due to efficacy, perceived safety, and cost effectiveness (generic, minimal monitoring), clinicians should be aware of potential adverse psychiatric manifestations