Chuanxiong Chajiao San has the effect of draining wind and relieving pain, and can treat headaches caused by external wind evils. Headaches are classified into cranio-cerebral lesions, extra-cranial lesions, and systemic diseases. The use of this product is prohibited for cranio-cerebral lesions visible as meningitis, cerebral hemorrhage, and high blood clots, because the headaches that occur in these diseases are not headaches caused by wind evil in TCM. The headache caused by the wind in TCM is similar to the headache caused by extracranial blood vessels in Western medicine caused by vasoconstriction or the headache caused by cold weather and rain and water. It should not be taken at the same time with other western medicine for headache. If you are taking other medicine for headache, you need to stop taking it before using this product. If headache is caused by high blood pressure or other diseases, this product should be used under the guidance of herbalists.