Patient education: Muscle spasms (muscle cramps) (The Basics)

What are muscle spasms? — A muscle spasm (or muscle cramp) is when a muscle suddenly tightens and can't relax. A spasm can happen to any muscle in the body. But it is most common in the calves and feet.

The exact cause of muscle spasms is unknown. They can happen at any time. But they are most common during exercise, especially when the muscles are tired or "fatigued."

Some experts believe that losing a lot of water and electrolytes can make cramps more likely. Electrolytes include sodium, potassium, magnesium, and calcium. Normally, the body has a specific balance of electrolytes. If a person loses a lot of fluid through vomiting, diarrhea, or heavy sweating, it can lead to problems.

Sometimes, other things, like taking certain medicines, can cause muscle spasms.

What are the symptoms of a muscle spasm? — Muscle spasms can be mild or severe. A mild spasm might feel like a twitch, while a severe spasm can be very painful. In some cases, you might be able to see the muscle twitching or cramping. The muscle might also feel hard to the touch.

Muscle spasms can last from a few seconds to up to several minutes.

Some people have leg cramps that happen at night. These are called "nocturnal" leg cramps.

Will I need tests? — Probably not. Your doctor or nurse will learn about your symptoms and do an exam. In some cases, they might order tests to check your electrolytes.

Can muscle spasms be prevented? — Muscle spasms can't always be prevented. But there are some things you can do to lower the chances of having them:

●Stay well hydrated – This is especially important if you are exercising for a long time, if you are doing very hard exercise, or if it is hot and humid. Drink plenty of water or sports drinks. Your doctor or nurse can talk to you about how to hydrate properly for your activities.

●Avoid exercising in very hot or humid weather, if possible – You can check the "heat index" for your local weather forecast. This estimates how hot it will feel outside based on the temperature and humidity.

How are muscle spasms treated? — When you have a muscle spasm, you can:

●Slowly stretch the affected muscle – For example, you can learn stretches for your calf (picture 1), your hamstring (picture 2), or your foot (figure 1).

●Massage the muscle – You can do this with your hands, a massage tool, or a foam roller.

●Use heat – Take a hot shower or bath. You can also put a hot towel or heating pad (on the "low" setting) on the area.

●Ice the area – Put a cold gel pack, bag of ice, or bag of frozen vegetables on the muscle. Put a thin towel between the ice (or other cold object) and your skin. It is best to apply the ice when the muscle is slightly stretched. If your muscle starts to cramp again, remove the ice.

●Take pain-relieving medicines, if needed – Ask your doctor or nurse what you should take.

When should I call the doctor? — Call for advice if:

●Your muscle spasms are not getting better with the treatments above.

●You are having a lot of muscle spasms.

More on this topic

Patient education: Hypovolemia in adults (The Basics)
Patient education: Muscle strain (The Basics)
Patient education: Nocturnal (nighttime) leg cramps (The Basics)
Patient education: Heat stroke (The Basics)