Associated mood changes with naloxegol therapy for opioid-induced constipation in a patient with psychiatric disease

The objective of this clinical case report is to highlight unusual adverse effects brought on by naloxegol therapy in a patient with underlying psychiatric illness. The patient is a 68-year-old female, with a psychiatric history of bipolar disorder, who presented for chronic pain management and opioid-induced constipation. After failing other therapies, she was trialed on naloxegol on three separate occasions. She experienced mood lability with symptoms including agitation, confusion, irritability, hysteria and unprompted crying spells on each occasion. Notably, the drug manufacturer does not describe mood lability, nor the profound psychiatric manifestations outlined in our case report, as side effects of Naloxegol. Clinicians may consider judicious prescription of naloxegol when treating opioid-induced constipation in patients with pre-existing psychiatric co-morbidities.