Gabapentinoids for treatment of neuropathic pain: a medicines usage evaluation at the Groote Schuur Hospital Chronic Pain Management Clinic

Background: Neuropathic pain (NP), defined as pain caused by a lesion or disease of the somatosensory system, affects 6.9–10% of people worldwide. Pregabalin is currently recommended as a first line drug for NP in South Africa.Methods: A cross-sectional, retrospective, descriptive medicines usage evaluation (MUE) of pregabalin at Groote Schuur Hospital (GSH) Chronic Pain Management Clinic for the year 2017 was conducted. A MUE using a standardised data collection form was performed on 100 randomly selected patient folders. Data was summarised using descriptive statistics.Results: The majority of cases were women (76) with a mean age of 55.9 years (SD12.49). A diagnosis of NP was recorded in 58 folders and a “possible” diagnosis recorded in 7 folders. In 79 cases there was no mention of a tool/method used to diagnose NP. The most common condition diagnosed was chronic postsurgical pain with a neuropathic component (n = 16), followed by NP (n = 15). The most common initiating and current dose of pregabalin was 75 mg twice daily. In 56 patients, pregabalin was prescribed in conjunction with a tricyclic antidepressant (TCA) or selective noradrenaline reuptake inhibitor (SNRI). Patient education was documented as having taken place in 76 of cases.Conclusions: Based on this MUE we recommend the use of screening tools for the diagnosis of neuropathic pain, and a focus on the initiating dose of pregabalin. The use of a standardised assessment document and the interdisciplinary team input at this clinic appears to optimise prescribing of pregabalin in line with practice guidelines.