Chronic migraine is a debilitating neurological disorder that significantly affects patients' daily functioning, mental health, and quality of life. Management typically includes acute and preventive treatments, but effectiveness can be limited due to medication overuse or delayed onset of action. OnabotulinumtoxinA injections provide proven long-term preventive benefits, while Greater Occipital Nerve (GON) block offers rapid but short-term relief. Although both treatments are used individually, evidence on the combined effect is limited. This randomized controlled trial aims to evaluate the efficacy and safety of combining OnabotulinumtoxinA injections with GON block, assessing improvements in headache frequency, severity, and patient quality of life compared to single therapy.