Introduction: There are limited therapeutic options for individuals with fibromyalgia. The aim of this study is to analyze changes in health-related quality of life and incidence of adverse events of those prescribed cannabis-based medicinal products (CBMPs) for fibromyalgia.

Methods:  Patients treated with CBMPs for a minimum of 1 month were identified from the UK Medical Cannabis Registry. Primary outcomes were changes in validated patient-reported outcome measures (PROMs). A p-value of <.050 was deemed statistically significant.

Results:  In total, 306 patients with fibromyalgia were included for analysis. There were improvements in global health-related quality of life at 1, 3, 6, and 12 months (p < .0001). The most frequent adverse events were fatigue (n = 75; 24.51%), dry mouth (n = 69; 22.55%), concentration impairment (n = 66; 21.57%), and lethargy (n = 65; 21.24%).

Conclusion:  CBMP treatment was associated with improvements in fibromyalgia- specific symptoms, in addition to sleep, anxiety, and health-related quality of life. Those who reported prior cannabis use appeared to have a greater response. CBMPs were generally well-tolerated. These results must be interpreted within the limitations of study design.