Greater Occipital Nerve Blockade: Safety, Adverse Effects, and Patient Outcomes In 1577 Injections

Background and objectives: Greater occipital nerve (GON) blockade is used to treat primary and secondary headache disorders. The primary objective of this study was to establish the safety and frequency of adverse events associated with GON blockade. Secondary objectives included recording patient-reported outcomes to provide real world data on the utility and consistency of the intervention. Material and methods: We performed a service evaluation of 1577 injections performed in 861 patients over a ten-year period. Results and conclusions: Immediate complications were recorded in 32 cases, the most common of which was near-syncope. Delayed effects were reported in 145 cases, mostly commonly persistent pain at the injection site. Serious side effects were rare. Follow-up data was available for 733/861 first injections. 36% of these patients reported an excellent or good response, 25% a fair or minimal response, 35% no response, and 4% were worse. The median duration of effect was two months. We conclude that GON blockade, even if repeated multiple times, is a safe and potentially useful intervention.