A cross-sectional study of prescribing of antiseizure medication for the treatment of pain in Australia.

Background: Antiseizure medications, particularly gabapentinoids like pregabalin, are increasingly prescribed for pain management. Despite their growing use, evidence of their effectiveness for pain is mixed. This highlights the need for a clearer understanding of the prevalence and prescribing patterns of antiseizure medications in pain management.

Aim: To investigate the initiation of antiseizure medications in people with and without pain or epilepsy diagnoses and to explore the concurrent use of opioids.

Method: This cross-sectional study used deidentified primary care data from 542 general practices in Victoria, Australia. Descriptive statistics were used to analyze antiseizure medication prevalence, concurrent opioid use, and prescribing patterns by age and gender.

Results: We identified 171,619 primary care patients who initiated an antiseizure medication between January 1, 2018, and May 31, 2023, among whom 80.1% had pain without epilepsy. Pregabalin was the most commonly prescribed medicine (58.2%), followed by sodium valproate (7.0%), gabapentin (6.9%), and clonazepam (6.7%). Among younger patients (14-49 years old) with an epilepsy diagnosis, women were twice as likely as men to initiate topiramate (6.5% vs 4.4%) and lamotrigine (21.8% vs 11.4%), while men were more commonly initiated with sodium valproate (38.7% vs 18.9%).

Conclusion: Given the widespread off-label use of gabapentinoids and the potential for serious harm, further research is warranted to better understand their clinical and safety outcomes.