Health Topic

Muscle Cramps

Have you ever had sudden, painful cramps in a muscle? These muscle spasms (also called charley horse) are very common. Learn how to relieve the pain.

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Also called: Charley horse

Important: This page is general information, not medical advice. It does not recommend or prescribe any treatment. Always consult your doctor or pharmacist before starting, stopping or changing any medicine.

About Muscle Cramps

Muscle cramps are sudden, involuntary contractions or spasms in one or more of your muscles. They are very common and often occur after exercise. Some people get muscle cramps, especially leg cramps, at night. They can be painful, and they may last a few seconds to several minutes.

You can have a cramp in any muscle, but they happen most often in the:

  • Thighs
  • Feet
  • Hands
  • Arms
  • Abdomen
  • Area along your ribcage

Causes of muscle cramps include:

  • Straining or overusing a muscle. This is the most common cause.
  • Compression of your nerves, from problems such as a spinal cord injury or a pinched nerve in the neck or back
  • Dehydration
  • Low levels of electrolytes such as magnesium, potassium, or calcium
  • Not enough blood getting to your muscles
  • Pregnancy
  • Certain medicines
  • Getting dialysis

Sometimes the cause of muscle cramps is unknown.

Anyone can get muscle cramps, but they are more common in some people:

  • Older adults
  • People who are overweight
  • Athletes
  • Pregnant women
  • People with certain medical conditions, such as thyroid and nerve disorders

Muscle cramps are usually harmless, and they go away after a few minutes. But you should contact your health care provider if the cramps:

  • Are severe
  • Happen frequently
  • Don't get better with stretching and drinking enough fluids
  • Last a long time
  • Are accompanied by swelling, redness, or a feeling of warmth
  • Are accompanied by muscle weakness

You usually don't need treatment for muscle cramps. You may be able to find some relief from cramps by:

  • Stretching or gently massaging the muscle
  • Applying heat when the muscle is tight and ice when the muscle is sore
  • Getting more fluids if you are dehydrated

If another medical problem is causing the cramps, treating that problem will likely help. There are medicines that providers sometimes prescribe to prevent cramps, but they are not always effective and may cause side effects. Talk to your provider about the risks and benefits of medicines.

To prevent muscle cramps, you can:

  • Stretch your muscles, especially before exercising. If you often get leg cramps at night, stretch your leg muscles before bed.
  • Drink plenty of liquids. If you do intense exercise or exercise in the heat, sports drinks can help you replace electrolytes.

It sits within Bones, Joints and Muscles.

The lead U.S. institute for this subject is the National Institute of Arthritis and Musculoskeletal and Skin Diseases.

When to speak to someone. Reading about a topic cannot tell you whether it applies to you. Speak to a doctor or pharmacist if symptoms are severe, sudden, getting worse, or simply not going away — and seek emergency care immediately for chest pain, breathing difficulty, sudden weakness or confusion, or a serious allergic reaction.

Research on Muscle Cramps

207 studies areregistered for this condition on ClinicalTrials.gov, the U.S. National Library of Medicine's public registry. A selection is below — the links go straight to the registry entry, not to a summary of ours.

What a registered study does and does not mean. Registration means a study exists and has been declared publicly. It says nothing about whether the treatment being tested works, is safe, or is available to you. Many studies find no benefit — that is what research is for. Never seek out an experimental treatment on the strength of a registry entry alone.

Research currently under way

Research already completed

Study data from ClinicalTrials.gov, a service of the U.S. National Library of Medicine. Retrieved 2026-07-30. Registry entries are supplied by study sponsors and investigators; ClinicalTrials.gov does not verify their scientific validity. PocketsInfo is not affiliated with, and not endorsed by, the NLM or the NIH.

Where to read more

Rather than paraphrase, we point you to the primary sources. Every link below is to a government health agency, a national institute or a recognised medical body — grouped by what you are trying to find out.

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Treatments and Therapies

Related Issues

Clinical Trials

Medical subject headings

Clinicians and researchers index this subject under Muscle Cramp. These are the terms to use when searching medical literature.

This page is built from the MedlinePlus health topic record for Muscle Cramps, a service of the U.S. National Library of Medicine (NLM), National Institutes of Health. Information is from MedlinePlus.gov. PocketsInfo is not affiliated with, and is not endorsed by, the NLM or the NIH. Retrieved 30 July 2026.