The symptoms of headache after washing hair with hot water and not blow-drying it in time may be caused by cerebral vasospasm caused by the contraction of the blood vessels of the scalp in the cold. It is best not to be outdoors when the symptoms of headache appear, because the outdoor temperature is low, it is best to enter indoors, avoid getting cold and drink more plain water. You can dry your hair with a dry towel or blow your hair with the hot air of a hair dryer, and massage your scalp points with your hands, commonly used points such as the solar plexus. If the symptoms of headache do not ease, you need to take medication, there are two kinds of drugs commonly used. One is non-steroidal anti-inflammatory drugs, commonly used drugs such as acetaminophen tablets, ibuprofen tablets, etc.; another commonly used drugs such as tranquilizer capsules, Zhengtian pill, etc. When washing hair in the future, the water temperature should not be too high, it is best to blow dry your hair in time, do not sleep with wet hair, so as not to cause headaches and other uncomfortable symptoms.