Leg Cramps: Causes, Treatment, and Prevention

Medically Reviewed by Jabeen Begum, MD on February 06, 2024
8 min read

Nocturnal leg cramps are a tight, knotted feeling in your legs that happens at night. They can last several seconds to several minutes. If the cramp is severe, your muscle may be sore for days.

Leg cramps are different from restless legs syndrome. Both tend to happen at night, but restless legs syndrome causes discomfort and an urge to move instead of painful muscle cramps.

As much as they may hurt, leg cramps are harmless.

 

Experts don't know the exact cause of nighttime leg cramps. They could happen because your nerves send the wrong signals to your muscles. For example, your brain might mistakenly tell your leg to move while you dream. That confuses your calf muscles and causes them to contract.

You're more likely to have leg cramps if you:

  • Are 50 or older
  • Work your muscles too much
  • Sit too long without moving
  • Don't drink enough water
  • Stand too long on hard surfaces

Other health conditions can also raise your chances of leg cramps, including:

  • Diabetes
  • Neurological conditions like Parkinson's disease
  • Alcohol abuse
  • Low blood sugar
  • Some hormone disorders, such as hypothyroidism
  • Too much or not enough of certain chemicals in your body, such as calcium, potassium, and magnesium
  • Flat feet
  • Pregnancy
  • Blood flow problems
  • Nerve damage

Talk to your health care provider about helpful and safe medications if home remedies like staying active, eating a vitamin- and mineral-rich diet, drinking plenty of water, and stretching before exercise don't ease your cramps. 

Another reason it's wise to consult your doctor: Leg cramps can be a warning sign of deep vein thrombosis (DVT), in which dangerous blood clots form in your leg.

Leg cramps and diabetes

People with type 2 diabetes are highly prone to muscle cramps, particularly in their legs. Such cramps can be severe, even disabling. They most often occur at night. Often, there's no explanation for why your cramps occur. However, possible causes include:

  • Nerve damage, called diabetic neuropathy, affects about half of people with diabetes. It typically starts in your legs and feet and can trigger cramps as well as sharp pain.
  • Peripheral artery disease (PAD). Diabetes ups your risk of PAD, which causes a fatty substance called plaque to build up and block blood flow in the arteries in your legs. One of the earliest symptoms of PAD is leg cramps.
  • Electrolyte imbalance. Electrolytes, which include calcium, potassium, magnesium, and other minerals, help your muscles work properly. When your blood sugar rises, your electrolytes drop. This can cause cramping.
  • Low blood sugar (hypoglycemia).

Talk to your doctor if you experience regular leg muscle cramps. They could be a warning sign of diabetes.

Medications that cause leg cramps at night

Several drugs can trigger leg cramps. They include:

  • Albuterol/Ipratropium (Combivent), which is prescribed for chronic obstructive pulmonary disease (COPD)
  • Celecoxib (Celebrex), a pain medication commonly prescribed for arthritis pain.
  • Clonazepam (Klonopin), which is used to treat seizure disorders and panic disorder
  • Conjugated estrogens (Premarin), which is used to treat hot flashes and other symptoms of menopause, as well as to prevent osteoporosis after menopause
  • Diuretics, also known as water pills, which treat many health conditions, including high blood pressure and heart failure
  • Fluoxetine (Prozac), an antidepressant
  • Gabapentin (Neurontin), which helps control seizures in epilepsy, reduce shingles-related nerve pain, and relieve restless legs syndrome
  • Naproxen (Naprosyn), a prescription painkiller
  • Pregabalin (Lyrica), which treats nerve pain and helps manage seizures in epilepsy
  • Sertraline (Zoloft), an antidepressant
  • Statins, a class of drug used to lower cholesterol
  • Zolpidem (Ambien), a sleep aid

Leg cramps at night in pregnancy

If you're pregnant, you've got about a 50% chance of developing leg cramps. They typically happen in the second and third trimester and most often strike at night. Experts aren't sure why they happen, but here are a few possible explanations:

  • Too little calcium and magnesium during pregnancy
  • Changes to the way your blood circulates
  • Weight gain leading to muscle strain
  • Dehydration

If you often have severe leg cramps, talk to your doctor, who can determine what's causing them.

You will be asked about your medical history and your symptoms. You'll likely talk about your current medications in case one of them could be the culprit. You may also undergo a physical exam to look for possible causes of your cramps. For example, your doctor will examine your legs for telltale signs of blood-flow problems, such as swelling and varicose veins. You likely will undergo both blood and urine tests to help your doctor spot less obvious problems and to rule out possible causes. 

These tests may include:

  • Blood glucose (sugar)
  • Hemoglobin A1c test, which measures your average blood sugar level over the past 3 months
  • Complete blood count
  • Blood tests that measure your electrolytes, such as iron, sodium, potassium, and calcium
  • Creatinine, a urine test that helps evaluate how well your kidneys are working
  • Thyroid-stimulating hormone, a blood test to check on the functioning of your thyroid gland

The next time a leg cramp strikes, try some of these tips:

  • Stretch the muscle.
  • Get out of bed and stand with your foot flat on the floor. Press down firmly.
  • Massage the muscle.
  • Flex your foot.
  • Grab your toes and pull them toward you.
  • Ice the cramp.
  • Take a warm bath.

Your doctor might give you medications such as diltiazem (Cardizem), diphenhydramine (Benadryl), or verapamil (Calan, Verelan). But they don't always work, and they can have harmful side effects. For example, experts used to use the anti-malaria drug quinine for leg cramps. Doctors and the FDA no longer recommend it because it can also cause severe bleeding and problems with your heart rhythm.

Vitamins for leg cramps at night

Could you ease your leg cramps with vitamin supplements? Some research does suggest that certain vitamins and minerals could provide relief.

  • Vitamin B complex. At least one study found this combination effective. It contains 8 different B vitamins, including B1 (thiamine), B2 (riboflavin), B3 (niacin), B5 (pantothenic acid), B6, B7 (biotin), B9 (folate), and B12.
  • Vitamin D. Very low levels of vitamin D may contribute to muscle cramps. However, research shows that vitamin D supplements do not effectively treat muscle cramps, at least not in pregnant or postmenopausal people.
  • Potassium. Low levels of potassium can make it hard for your muscles to relax, and that can cause a cramp. Eating potassium-rich foods, like bananas and black beans, might help. You might require potassium supplements if you have low potassium, but don't take them without talking to your doctor first.

Magnesium for leg cramps

It's unlikely that magnesium supplements will help your leg cramps, according to the latest expert reviews of the research. Some research does suggest that magnesium supplements could reduce the number of leg cramps you have at night, but the findings on magnesium's effectiveness are mixed.

Some simple things might keep you from getting leg cramps:

  • Stretch during the day and before bed. Focus on your calf and foot muscles.
  • Drink plenty of water.
  • Move around during the day to exercise your feet and legs.
  • Wear comfortable, supportive shoes.
  • Sleep under loose covers, especially if you sleep on your back.

 

Everyone has the occasional leg cramp. Painful as they may be, leg cramps usually pass quickly and are rarely something to worry about. But you should see a doctor about your legs cramps if:

  • They cause significant pain.
  • They occur frequently, waking you up at night and preventing you from getting good sleep.
  • You develop muscle cramps in other parts of your body.
  • You develop swelling, numbness, or skin changes in your leg.

Some symptoms or circumstances require a trip to the emergency room. These include:

  • Debilitating pain
  • Cramps that last more than 10 minutes
  • Cramps that develop after you come into contact with a hazardous substance, such as mercury, lead, or other toxic substance
  • Cramps that develop if a cut on your leg comes into contact with something that could cause infection. For example, dirt can harbor bacteria that cause tetanus.

Stretching your leg muscles can relieve your cramp quickly. In fact, some research shows that nightly stretching exercises also can help prevent leg cramps or reduce the amount of pain they cause. Here are some stretches you should try:

  • Calf stretch. You can do this one standing, sitting, or even while in bed. Straighten your leg and pull your toes up and toward your shin. If you can't reach your toes with your hands, no problem. Wrap a towel around your toes and pull the towel up. You will feel this stretch in your calf muscle.
  • Lower front leg stretch. Standing up, lift your heels off the floor while putting your weight on your toes.
  • Hamstring stretch. This can help cramps that occur in the back of your upper legs, known as your hamstring muscles. Sit on the floor with your legs extended and straight in front of you. Slowly lean forward as your hands slide down the sides of your legs. Stop when you feel a burning sensation coming from the cramped muscle. Remain in that position for 30 seconds, then slowly ease your way back to your starting position.
  • Quad stretch. This may help relieve cramps in the front muscles of your upper legs. Stand up and hold on to a chair to maintain your balance. Then, lift one foot up and back toward your butt.

Nocturnal leg cramps strike suddenly--and painfully. Despite the pain, they're harmless and pass quickly. However, some leg cramps can signal serious health issues or be a side effect of medications that you take. Talk to your doctor if you experience leg cramps frequently, they disrupt your sleep, or they don't go away.

What deficiency causes leg cramps at night?

If you have low levels of certain minerals called electrolytes, you may experience leg cramps. These electrolytes include sodium, potassium, calcium, and magnesium.

What drink stops leg cramps?

Dehydration may raise your odds of getting leg cramps, so drink 6 to 8 cups of water a day to keep hydrated.

Does eating bananas help with leg cramps?

Maybe. If your cramps develop due to low levels of potassium, eating bananas or other foods high in potassium could help prevent cramps.