In this study we aim at investigating efficacy of prophylactic Lisinopril, an inhibitor ACE, in comparison with placebo in the alleviation of migraine headaches in patients with chronic migraine in a randomized, double-blind. The main objective of the study is to explore the effects of prophylactic Lisinopril vs. placebo in reducing the frequency and severity of chronic headache in migraineurs referred to specialized clinics. Other study objectives include comparing the effects of Lisinopril and placebo in reducing the use of medications during attacks, remission from chronic migraine to episodic migraine, improving migraine associated complications, and improving quality of life in the patients. 112 patients with chronic migraine will be recruited in a randomized double-blind clinical trial. After obtaining the informed consent form from patients, they will be randomly allocated to placebo group or Lisinopril 10 mg taking group. Patients will be included in the study due to the following inclusion Criteria: having ≥ 15 headache days per month for at least 3 months, history of migraine for at least 1 year, age 18-45 years, systolic blood pressure between 110-140 mmHg and taking a large amount of abortive drugs. . The exclusion criteria were as follows: having psychiatric illness, having major neurological disorders and / or other chronic or systemic diseases, being pregnant or have a planned pregnancy, breastfeeding, taking prophylactic medications in the last 4 weeks, suffering from impaired liver function or kidney disorders, allergies to ACE inhibitors, history of angionearotic edema and suffering from secondary headaches. will be asked not to continue any previous medication for migraine . At the same time with prophylactic treatment (lisinopril or placebo) in both groups, 4 capsules of Celebrex 100-milligram per day, thereafter the dosage will be reduced by 100-mg (1 capsule) each 5-day to zero over the first 20 days of the study. Duration of the study will be 12 weeks and headache characteristics as well as drug response and quality of life will be assessed in the second week and at the end of each month during the study.