Night leg cramps happen when leg muscles suddenly tighten during sleep. They're also called nocturnal leg cramps. Night leg cramps usually involve calf muscles, although muscles in the feet or thighs might cramp as well. Stretching the tight muscle with force can relieve the pain.
Most of the time, there's no known cause for night leg cramps. In general, they're likely the result of tired muscles and nerve problems.
The risk of having night leg cramps increases with age. Pregnant people also are more likely to have night leg cramps.
Kidney failure, diabetic nerve damage and problems with blood flow are known to cause night leg cramps. But if you have one of these conditions, you probably already know. And you likely have symptoms other than just night leg cramps.
People who take medicines that increase urine output might be more likely to have night leg cramps. But it's not known if there's a direct link.
Restless legs syndrome is sometimes confused with night leg cramps. But the conditions are different. The most common symptom of restless legs syndrome is the need to move the legs when falling asleep. Restless legs syndrome is usually not painful, and the symptoms last longer than do night leg cramps.
Other health issues that can sometimes be linked to night leg cramps include:
For most people, night leg cramps are just a bother — something that jerks them awake sometimes. But some people who have them might need to see a health care provider.
To help prevent night leg cramps, try to:
To relieve night leg cramps, try to:
