I have a headache the day after drinking red wine. First of all, it is considered that alcohol contains traces of hashish oil, which is a substance toxic to the body and therefore causes headache symptoms. In addition, the blood flow to the brain is reduced after drinking alcohol, which then causes the accumulation of lactic acid, chloride ions, potassium ions, as well as adenosine and prostaglandins in the brain, which are not metabolized the day after drinking alcohol, causing the blood vessels in the brain to dilate, resulting in head pain. Secondly, blood pressure should be measured the day after drinking to see if the patient has a headache due to elevated blood pressure. For headaches that often occur after drinking alcohol, Pingsu recommends that patients drink more brown sugar water after drinking alcohol, and also more honey water, and sometimes more rice soup water, to promote the metabolism and transformation of alcohol in the body.