Retrospective Chart Review: The Feasibility of a Self-Administered Nasal Spray Targeting the Sphenopalatine Ganglion (SPG) in Treatment of Chronic Migraine.

Abstract

Objective: To describe the results of a self-administered anesthetic nasal spray developed to target the sphenopalatine ganglion (SPG) for the acute and preventive treatment of chronic migraine. Background: The SPG is a known migraine treatment target that may be anesthetized via minimally invasive in-office procedures. Historically, various noninvasive selfadministered intranasal anesthetic formulations have been developed for the treatment of migraine, with some studies suggesting implication of the SPG mechanism, however, this has needed further development and data on efficacy has been mixed and inconclusive. During COVID-19 pandemic clinic closures, we noticed a substantial need for improved at-home therapies for our university headache center patients with chronic migraine. Methods: We developed a compounded anesthetic nasal spray utilizing upward force and a supine delivery positioning with the aim of better targeting the SPG. Patients were instructed to use this treatment once per month as prevention and, additionally, up to four times per month as need acutely. Retrospective chart review was performed. Physician clinical judgment of patient reports was used to assign a dichotomous conclusion of the usefulness of such treatment for patients at an interval of 3 months (preventive effect) and acutely (acute effect). Adverse effects were also reviewed. Results differentiate treatment response in medication overuse headache (MOH) and peripartum subgroups as well. Results: 52 out of 66 (79%) patients reported improvement in overall headache frequency or intensity at 3 month follow up (preventive effect). 40 out of 53 (75%) patients who using the treatment acutely reported improvement in headache intensity (acute effect). Of the 6 patients also with MOH, 5 (83%) reported preventive effect and 4 (67%) reported acute effect. Of the 9 patients who were also peripartum, all 9 (100%) reported preventive effect and 8 (89%) reported acute effect. No significant adverse effects were reported. Conclusion: A self-administered nasal spray developed to target the SPG may be an effective and safe therapy for the acute and preventive treatment of chronic migraine. This delivery method suggests safe and potentially successful blockade of the SPG at home. Further developments in non-invasive intranasal techniques are warranted.