Headache caused by dehydration is mainly to give rehydration as symptomatic to replenish blood volume to reduce and eliminate this dehydration-induced headache. Patients should try to rest in bed as much as possible, keep the head as low as possible, and drink more water, preferably light saline or juice for hydration. If the headache is not relieved, dehydration can also be reduced by simultaneous intravenous administration of saline, such as sodium chloride, compound sodium chloride, glucose solution, etc. Dehydration headache mainly occurs because when the temperature is higher, the body also evaporates more sweat and drinks relatively less water, there will be dehydration, which will cause headache.