While most causes of feeling hot and eye pain can be treated at home, if your toddler's temperature is more than 102 degrees F or he exhibits other symptoms such as red or swollen eyes or a rash, consult your pediatrician immediately. Your child may be suffering from overexertion, excessive sun exposure or infection from a virus or bacteria.
According to MayoClinic.com, your child's temperature fluctuates during the day. While often lower in the morning, body temperature tends to rise late. As your child exercises, the capillaries under his skin expand to allow more blood to flow to the surface, where it can be cooled by air temperature and sweat. The increased blood flow can cause him to feel hot. If he is tired, he might complain his eyes hurt as well. If he is dehydrated, he may get a headache that can be described as pain behind her eyes.
If your child gets too much exposure to the sun or hot, humid temperatures, he could develop sunburn, heat cramps or heat stroke. Sunburn occurs when your child's skin is exposed for too long and causes your child's skin to become red and hot. Your child's eyeballs can become sunburned as well and can feel painful or gritty. Heat cramps occur when your toddler becomes overexerted in hot weather. His skin may be hot and sweaty and he may develop cramps in his stomach, arms or legs. Fatigue from overexertion can cause his eyes to hurt. If left untreated, heat cramps can progress to heat stroke, a life-threatening condition that occurs when your child's body temperature rises above 104.
While most fevers are temporary and harmless, consult your pediatrician if your toddler's temperature rises above 102 degrees or does not subside after about 72 hours. According to MayoClinic.com, fever can be due to an infection, heat exhaustion, sunburn, some medications and immunizations. Symptoms of the flu include fever and eye pain. Excessive physical exertion, bathing and too much clothing can also cause a temporary fever.
Other, less common but more serious causes of a child being hot and having eye pain include periorbital cellulitis, an eye infection that can occur in children under 6, and temporal arteritis, an inflammation to the blood vessels that usually occurs after age 50 but can affect children.