Doctors Link Antibiotic to Rare Cotard Syndrome
A case report details how an antibiotic caused a rare delusion in a patient with kidney disease.
Updated on Oct. 30, 2026 in Alzheimer’s
Medical professionals have identified the antibiotic cefepime as the cause of Cotard syndrome in a 76-year-old patient. The patient, who suffered from end-stage kidney disease, recovered after the medication was discontinued and dialysis was performed.
Why it matters
The case highlights the severe neurotoxic risks of cefepime when administered to patients with compromised renal function. Because the kidneys typically filter 85% of the drug, failure to adjust dosages can lead to dangerous accumulation and neuropsychiatric side effects.
Medical data indicates that 85% of cefepime is excreted by the kidneys, and 80% of neurotoxicity cases occur in patients with renal dysfunction. An FDA review previously identified 59 cases of nonconvulsive status epilepticus related to the drug.
The players
U.S. Food and Drug Administration
The federal agency responsible for protecting public health by ensuring the safety, efficacy, and security of human and veterinary drugs.
Annals of Internal Medicine
A prestigious peer-reviewed medical journal published by the American College of Physicians.
The details
Doctors performed an electroencephalogram on the patient that revealed a pattern consistent with toxic-metabolic encephalopathy. Following the diagnosis of cefepime-induced Cotard syndrome, medical staff successfully resolved her symptoms by stopping the antibiotic and initiating dialysis to remove the drug from her bloodstream.
Timeline
1880: Jules Cotard provides the initial description of the syndrome.
1996 through February 2012: The FDA identifies 59 cases of nonconvulsive status epilepticus.
2012: The FDA issues a formal Drug Safety Communication regarding cefepime.
August 2025: A case study regarding the patient is published in the Annals of Internal Medicine.
Health Landscape
This case follows the pattern of neurotoxicity concerns highlighted by the 2012 FDA Drug Safety Communication on cefepime seizure risk. It illustrates the ongoing challenge of managing drug dosages in populations with end-stage renal disease to prevent toxic accumulation.
Patients with kidney dysfunction should discuss the risks of cephalosporin antibiotics with their providers to ensure proper dosing. Caregivers and clinicians should monitor for sudden neuropsychiatric changes in individuals receiving medication for infections.
The takeaway
This case serves as a critical reminder that even common antibiotics can produce rare and severe psychiatric side effects in high-risk patients. Clinicians should maintain a low threshold for suspecting drug-induced toxicity when patients present with sudden, unexplained behavioral changes.
Further reading
For more information on the latest research, visit the Alzheimer’s section.
Source note: This article includes information reported by Medical Daily.
