Heat Reactions

Definition

• Symptoms after being in high temperatures (such as heat waves)
• Symptoms after hard work or sports during hot weather
• Heat cramps, heat exhaustion and heatstroke are covered

Call or Return If

• Vomiting keeps from drinking
• Signs of dehydration occur
• Muscle cramps last more than 4 hours
• Fever goes above 104°F (40.0°C)
• Fever lasts more than 2 hours
• You think your child needs to be seen
• Your child becomes worse

About This Topic

Types of Heat Reactions

• There are 3 main reactions to hot temperatures and heat waves.
• Heatstroke or Sunstroke. Symptoms include hot, flushed skin with high fever over 105° F (40.5° C). Over 50% of children with heatstroke do not sweat. Heatstroke can cause confusion, coma or shock. Heatstroke is a life-threatening emergency. Call 911.
• Heat Exhaustion. Symptoms include pale skin, profuse sweating and nausea. Dizziness, fainting, or weakness can also be signs. Can have a mild fever 100 - 102° F (37.8 - 39° C) for a short time. Most of the time, there is no fever. Most of these symptoms are caused by dehydration from sweating. A person can progress from heat exhaustion to heatstroke. So, all patients with severe symptoms (such as fainting) need to be seen now. Mild symptoms (such as dizziness) can be treated at home with fluids and rest. But, if these don't resolve with treatment, these children also need to be seen.
• Heat Cramps. Severe muscle cramps in the legs (calf or thigh muscles) and stomach are present. No fever. Tightness or spasms of the hands may occur. After your child drinks fluids and cools down, he or she will feel better. All symptoms should go away in a few hours.

Causes

• All 3 reactions are caused by exposure to high temperatures often with high humidity.
• Exertion. During hot weather, hard work or sports can cause heat production to exceed heat loss.
• Dehydration. Poor hydration interferes with sweating. That increases the risk of heat reactions.
• Babies are at more risk because they are less able to sweat when hot.
• Heat waves. The first heat wave of the summer can cause heat problems. It takes 8 to 10 days for you to become used to high summer temperatures. This can also happen on vacations.
• Exposure to a very high temperature. It usually follows exposure to a very high temperature. Examples are being inside a hot car or in a steam tent. Being indoors without air-conditioning during heat waves is also the main cause of heat stroke in the elderly.
• Health and risk factors. Babies are less able to sweat when hot. Obese children also have a decreased ability to give off heat.

Prevention Of Heat Reactions

• Drink more water. When working or exercising in hot weather, have your child drink large amounts of cool water. This helps to prevent dehydration. For teens, this means at least 8 ounces (240 ml) every 15 to 30 minutes. Water is the ideal liquid for replacing lost sweat. Very little salt is lost.
• Sports drinks. Most often, special sports drinks offer no advantage over water. But, they are helpful if working out for longer than an hour. If that is the case, replace 1 water drink per hour with a sports drink.
• Take water breaks. Try to do this every 15 minutes in the shade. Drink some water even if you are not thirsty. Thirst can be delayed until a person is almost dehydrated.
• Avoid salt tablets. They slow down stomach emptying and delay the absorption of fluids.
• Dress cool. Wear a single layer of lightweight clothing. Change it if it becomes wet with sweat. Children need the same layers of clothing as an adult. Be extra careful of babies in hot weather. Do not overdress them.
• Exercise smart. Physical activity in hot weather should be increased slowly.
• Stay cool. During heat waves, spend as much time as possible inside with air-conditioning. Electric fans also help. Slow down. It takes at least a week to get used to hot summer temperatures.

After Care Advice