HealthInfo Waitaha Canterbury
Leg cramp
Parerori waewae
Leg cramp is common and harmless but can be very painful. It usually happens at night or when you're resting.
A cramp is when a muscle contracts then doesn't relax. It can last from a few seconds to 15 minutes and may happen several times before going away completely.
Causes of leg cramp
Often there is no clear reason for leg cramp, but possible causes include:
- a tired muscle from exercise or overuse
- not drinking enough fluids (dehydration)
- some medications, such as diuretics
- pregnancy
- alcohol
- an imbalance of body salts (electrolytes) such as sodium, calcium and potassium.
Diagnosing leg cramp
If you have frequent leg cramps, you should see your general practice team to check if there is an underlying problem.
They will examine your legs and do blood tests.
Treating leg cramp
You can stop most muscle cramps if you stretch the muscle, either by standing up, massaging or by applying cold packs.
Stretch and massage a cramped leg by straightening it and pointing your toes upward, while gently rubbing the cramped area to help the muscle relax. For a calf cramp, put your weight on the affected leg and bend your knee slightly. For a thigh cramp, keep both legs straight and lean forward at your waist, using a chair to steady yourself.
Preventing leg cramp
- Stretch every day. Stand about 1 metre from a wall and lean into the wall to rest on the palms with your legs straight and feet flat on the floor. This stretches your calf muscles. Hold for 10 to 20 seconds, then rest. Repeat 3 to 4 times before bed.
- Keep your bedding loose around your feet and legs.
- Reduce or avoid caffeine or alcohol.
- Keep drinking enough to avoid dehydration.
- Magnesium supplements may help pregnant women.
Quinine used to be recommended for cramp but is not any more as it can have serious side effects.
HealthInfo recommends the following pages
- NHS – Leg cramps
A short guide to leg cramps, what causes them and how they can be treated.
Written by HealthInfo clinical advisers. Last reviewed October 2022.
SourcesReview key: HISLE-11928
