Abstract Background Fibromyalgia is a complex pain-focused syndrome. Previous studies showed that Cannabis is efficacious in promoting sleep, deepening and lengthening the sleep cycle, and good pain relief (compared with the SSRIs and SNRIs). Purpose This study aimed to use the World Health Organization Quality of Life Bref questionnaire (WhoQoL-bref) to characterize the impact of Cannabis Treatment initiation on the quality of life in women suffering from treatment-resistant fibromyalgia. Methods A prospective cohort study involving 30 women aged 18–70 years old diagnosed with fibromyalgia, exhausted pharmacological fibromyalgia treatment, and started Cannabis treatment. Pregnant women were excluded. WhoQoL-bref was filled before Cannabis treatment initiation and 1 month...