Heat Cramps

Heat Cramps Overview

Heat cramps are painful, brief muscle cramps. Muscles may spasm or jerk involuntarily. Heat cramps can occur during exercise or work in a hot environment or begin a few hours later.

Heat cramps usually involve muscles that are fatigued by heavy work such as calves, thighs, and shoulders.

• You are most at risk if you are doing work or activities in a hot environment-usually during the first few days of an activity you're not used to.
  
  
• You are also at risk if you sweat a great deal during exercise and drink large amounts of water or other fluids that lack salt.

Heat Cramps Causes

The exact cause of heat cramps is unknown. They are probably related to electrolyte problems. Various essential minerals, such as sodium, potassium, calcium, and magnesium, are known as electrolytes. They undergo chemical changes in your tissues. An imbalance can cause problems.

Sweat contains a large amount of sodium, and drinking fluids with inadequate sodium content may result in a serious low-sodium condition called hyponatremia. Some factories have virtually eliminated heat cramps in their workers by supplying salt-enriched fluids.

Heat Cramps Symptoms

Muscle spasms

• Painful
  
  
• Involuntary
  
  
• Brief
  
  
• Intermittent
  
  
• Usually self-limited (go away on their own)

When to Seek Medical Care

Heat cramps can be quite painful. Consider seeking medical attention if the symptoms do not go away with rest and after restoring fluid and electrolytes.

Call your doctor if these conditions develop:

• If you are unable to drink sufficient fluids because you have nausea or are vomiting, you may need IV rehydration with normal saline.

• Rarely, heat cramps can accompany heat exhaustion. If so, call the doctor.

• If you have more severe symptoms of heat illness, including dizziness, fatigue, vomiting, headache, malaise, shortness of breath, and high temperatures (greater than 104°F), call the doctor for instructions.

If you have more severe forms of heat illness or require IV fluids to rehydrate, seek care at a hospital's emergency department.

Heat Cramps Treatment

The doctor will check you for more severe heat illness and possibly provide you with IV fluid rehydration.

Self-Care at Home

Heat cramps usually go away whether you do anything or not. They respond to home care.

Rest in a cool place and drink fluid mixed with salt.

• Make your own salt solution by mixing 1/4 to 1/2 teaspoon table salt dissolved in a quart of water.
  
  
• Commercially available electrolyte beverages will provide adequate dietary salt intake, too.
  
  
• Salt tablets by themselves should not be used. They can cause stomach upset and don't adequately replace fluid volume lost.

Next Steps Prevention

If you work in a hot environment, you may experience heat cramps during the first few days of that work. Once you get used to the environment, and make sure you have adequate salt-fluid replacement, you should have no further problems.

Outlook

Heat-induced muscle spasms usually go away on their own.