Thanks for the query. If there is a high temperature then dehydration is quite common and its very important for us to keep in mind that even mild dehydration can have adverse effects on mood and energy. That’s why it’s so important to catch dehydration early on, but the signs aren’t always obvious ones like thirst and fatigue. It can lead to bad breath, muscle cramps, dry skin, fever & chills, food cravings & headaches. Headaches. The brain sits inside a fluid sack that keeps it from bumping against the skull. If that fluid sack is depleted or running low because of dehydration, the brain can push up against parts of the skull, causing headaches. I advise you to drink lots and lots of water, avoid yourself going outside or getting exposed to higher temperatures. Drink atleast 500 ml of water every hour to keep yourself sufficiently rehydrated. Automatically headache will come down. First take a tablet of Ibuprofen for immediate relief followed with water therapy to prevent future headaches and other bad effects of dehydration.