Muscle cramp

A muscle cramp is a sudden and involuntary contraction of one or more of your muscles. If you've ever been awakened in the night or stopped in your tracks by a sudden charley horse, you know that muscle cramps can cause excruciating pain. Though generally harmless, muscle cramps can make it temporarily impossible to use the affected muscle.

Long periods of exercise or physical labor, particularly in hot weather, may lead to muscle cramps. Some medications and certain medical conditions also may cause muscle cramps. You can usually treat muscle cramps at home with self-care measures.

Symptoms Causes Risk factors Prevention

Most muscle cramps develop in the leg muscles, particularly the muscles in the calf. In addition to the sudden, sharp pain, you may also be able to feel or see a hard lump of muscle tissue beneath your skin.

When to see a doctor

Muscle cramps usually disappear on their own and are rarely serious enough to require medical care. However, see your doctor if your cramps:

  • Cause severe discomfort
  • Are associated with leg swelling, redness or skin changes
  • Are associated with muscle weakness
  • Happen frequently
  • Don't improve with self-care
  • Aren't associated with an obvious cause, such as strenuous exercise

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