What are nocturnal leg cramps?
Nocturnal leg cramps are pains that occur in the legs during the night. They usually cause awakenings from sleep, but they may also occur while awake at night during periods of inactivity. These cramps mostly happen in the calf muscles but can also occur in the thighs or feet. Nocturnal leg cramps are quite painful and cause the affected muscles to feel tight or knotted. Symptoms may last from several seconds up to several minutes. There might also be muscle soreness after the cramp goes away.
Who gets nocturnal leg cramps?
Although anyone can get nocturnal leg cramps, the number of people who get them increases with age. Slightly more women than men experience these leg cramps.
Nocturnal leg cramps have been reported by:
- 50 to 60 percent of adults
- 7 percent of children and teens
- 40 percent of pregnant women
Some 20 percent of patients who experience nocturnal leg cramps on a daily basis seek medical attention.
Are nocturnal leg cramps the same as restless legs syndrome?
No. While both types of leg disturbances tend to happen at night, or at rest, restless leg syndrome does not cause severe, cramping pain. While restless legs syndrome can be painful, it is more of a discomfort, or a crawling sensation that results in a desire to move the legs. While moving, the restlessness is relieved, but the discomfort returns when movement stops. This does not happen with nocturnal leg cramps where the tightened muscle needs to be actively stretched out for relief.
What causes nocturnal leg cramps?
The cause of nocturnal leg cramps is often times unknown, but some cases have been linked to:
- Sitting for long periods of time
- Over-exertion of the muscles
- Standing or working on concrete floors
- Sitting improperly
Nocturnal leg cramps have also been linked to certain medical conditions and medications. These include:
- Narrowing of the arteries/circulation-related diseases
- Narrowing of the spinal canal in the lower back (lumbar canal stenosis), which can compress nerves that travel from lower back to legs
- Cirrhosis of the liver (scarring of the liver) due to alcoholism, hepatitis, or other causes
- Dehydration/electrolyte imbalances
- Parkinson’s disease
- Nerve damage from cancer treatment
- Kidney failure/hemodialysis
- Peripheral neuropathy
- Neuromuscular disorders (neuropathy, myopathy, motor neuron disease)
- Structural disorders (flat feet)
- Endocrine disorders (diabetes, hypothyroidism)
- Medications: IV iron sucrose, conjugated estrogens, raloxifene (Evista®), naproxen (Naprosyn®), teriparatide (Forteo®)