Journal of Pharmacovigilance

Abstract

Ertapenem-induced Neuropsychiatric Symptoms in an Elderly Patient with Chronic Kidney Disease Resulting to a Prescribing Cascade

Ferdinand Z Ribo and Annabelle A Ribo

Seizure as a rare but a major side-effect of carbapenems are widely reported in literature but non-seizure, neuropsychiatric events have scarce, limited information available.

Objectives: To present a case report of an elderly patient with chronic kidney disease who had neuropsychiatric effects during ertapenem therapy leading to additional prescribing of anti-psychotic/sedating medications to manage adverse drug events.

We present a case of an 85 year old female patient without prior CNS disorder who developed visual hallucinations, agitation, disorientation, sleeplessness after 3 days of ertapenem 1 g therapy. The patient was prescribed with quetiapine and valproic acid to initially manage restlessness and donepezil was later added. Ertapenem was discontinued after day 7 of therapy while agents to manage agitation were continued. Based on the Naranjo score (6), the manifestations of hallucinations, agitation, sleeplessness were probable adverse drug reactions of ertapenem. Associated risk factors were excessive dose, advanced age and renal dysfunction. With a creatinine clearance of 30 ml/min, the recommended dose is 500 mg daily. Two days after ertapenem was discontinued, the symptoms abated. There was a noted decrease of hallucination, disorientation, restlessness and patient was slowly able to sleep. On the 13th hospitalization day, there was no restlessness, only episodes of confusion. Patient was discharged on the 15th hospitalization day with discharge medications for valproic acid, donepezil and alprazolam.

Conclusion: Ertapenem may exhibit non-seizure neurotoxicity if used beyond recommended dose. Adverse drug events from inappropriate use of drug are associated with patient harm, longer hospitalization and more medications which we were preventable in the first place. To our knowledge, this is the first probable adverse drug reaction from ertapenem documented in the Philippine setting.