Immediate release fentanyl in general practices: Mostly off-label prescribing

BACKGROUND: The immediacy of the onset of opioids may be associated with the risk of dependency and accidental overdose. Nasal and oromucosal fentanyl dosage forms are so called immediate release fentanyl (IRF). These IRFs have been approved to treat breakthrough pain in patients with cancer who are on chronic opioid treatment only. There are signals of increased off-label prescribing of IRFs in general practices. OBJECTIVES: This study aims to provide insight into the frequency of IRF prescription in Dutch general practices and the extent to which IRF is prescribed off-label. METHODS: Routinely collected electronic health records of general practices (GPs) participating in Nivel Primary Care Database were used. Adult patients with IRF prescriptions in 2019 were selected from whom dispensing data on 2018 and 2019 was available. Diagnoses were recorded by GPs using International Classification of Primary Care. Descriptive analyses were performed. RESULTS: This study included 342 GPs with a patient population of 1,297,942 patients, 1,368 patients received at least one IRF prescription in 2019, which is equal to 1.1 patients per 1,000 registered patients. Most patients (74.9%) with an IRF prescription received an off-label prescription. A slight majority had a cancer diagnosis but nearly 65.2% did not have a maintenance therapy and 14% were opioid-naive before receiving their first IRF prescription. CONCLUSION: IRFs are not prescribed frequently in Dutch general practices. However, when prescribed, a relatively large portion of patients received an off-label prescription.