An Unusual Amnestic Syndrome Associated With Combined Fentanyl and Cocaine Use

TO THE EDITOR:

Duru and colleagues (1) highlight a potential confounder when evaluating patients for new-onset amnesia. Because of the pervasive expansion of opioid use disorder in our society, this condition must now be considered in every avenue of medicine. However, nonmedical use of opioids-and even the basic pharmacology of these agents-is a complex issue. Many if not most persons who abuse opioids simultaneously abuse other substances. The authors thoroughly addressed concomitant use of various opioid derivatives, cocaine, and even synthetic opioids; however, they did not discuss gabapentin, which is frequently concomitantly abused with opioids (2) to potentiate the opioid effect (3). Patients receiving combination therapy with gabapentin and opioids often have more adverse events, including cognitive dysfunction (4). As a drug commonly abused with opioids for which memory loss is a known adverse effect (5), gabapentin should be considered when evaluating the amnestic syndrome reported by Duru and colleagues.