Opioid withdrawal syndrome developing after long-term administration of naldemedine.

ABSTRACT

OBJECTIVE: One of the side effects of opioid administration is opioid-induced constipation (OIC). To address this side effect, the oral peripheral µ opioid receptor antagonist naldemedine was developed. As this drug does not cross the blood-brain barrier, it is thought that it does not lead to opioid withdrawal syndrome (OWS) with central nervous system symptoms. METHODS: Here, we report a cancer patient who presented with symptoms centered round anxiety and irritation 4 months after administration of naldemedine for OIC and who was diagnosed with OWS after close investigation. RESULTS: The patient was a 65-year-old female who had surgery for stage IB endometrial cancer 4 years previously, but experienced recurrence involving the pelvis 2 years later. Medical narcotics were used to control pain, but naldemedine was started to control subsequent constipation. When naldemedine-related OWS was suspected and the administration of naldemedine discontinued, the above symptoms disappeared within two days, and no recurrence was observed thereafter. SIGNIFICANCE OF THE RESULTS: For patients receiving naldemedine, it is necessary to consider the possibility of OWS regardless of the period of administration in order to maintain patient quality of life.