10. Dehydration
Fever can cause dehydration, which then leads to a variety of serious complications. Dehydration can lead to a dry mouth, dry eyes, irritated skin, digestion problems, and even headaches. This is due to the brain shrinking, and then pulling away.
It is important to keep your child hydrated if they are sick, especially if the illness coincides with an infectious disease. You may find it difficult to get your child to drink water if they are irritable and have lost their appetite.