Sun poisoning can be a real pain in the neck. Literally. The symptoms – which include a headache, fever, and muscle cramps – are no fun at all. So how long does sun poisoning take to go away? Unfortunately, there's no easy answer. Depending on the severity of your sun poisoning, it could take anywhere from a few days to several weeks for the symptoms to disappear completely. But with some self-care and patience, you'll ...