Clinical Observation of Toutong Jieyu Tongluo Formula in Treating Primary Chronic Headache with Liver Qi Stagnation and Phlegm-Blood Stasis Obstructing the Collaterals Pattern

INTERVENTION: Chinese Medicine Group: Toutong Jieyu Tongluo Formula;Western Medicine Group: Flunarizine Hydrochloride Capsules (5 mg per capsule), 1 capsule nightly.; CONDITION: Primary Chronic Headache PRIMARY OUTCOME: Number of Headache Attacks;Headache Index; SECONDARY OUTCOME: Headache Associated Symptom Score;TCM score;Dependence on analgesics; INCLUSION CRITERIA: Patients who meet all of the following criteria are eligible for inclusion in this trial: (1) Meet the diagnostic criteria for primary chronic headache according to the International Classification of Headache Disorders, 3rd edition (ICHD‐III) established by the International Headache Society in 2018, including chronic migraine, chronic tension‐type headache, new daily persistent headache, and hemicrania continua; (2) Conform to the syndrome differentiation standard for headache with liver qi stagnation and phlegm‐blood stasis obstructing the collaterals; (3) Aged between 18 and 65 years; (4) Normal communication ability, comprehension capacity, and conscious state; (5) The patient and their family members have been informed and provided consent, and have signed the informed consent form.