Charley horse is another name for a muscle spasm. Charley horses can occur in any muscle, but they’re most common in the legs. These spasms are marked by uncomfortable muscle contractions.

If the contracting muscles don’t relax for several seconds or more, the pain can be severe. Severe charley horses can result in muscle soreness that lasts anywhere from a few hours to a day. This is normal, so long as the pain isn’t prolonged or recurring.

Charley horses are generally treatable at home, especially if they’re infrequent. However, frequent muscle spasms are often linked to underlying health conditions that need medical treatment.

Your doctor can help you determine the cause of frequent charley horses. And you can implement treatments and preventive measures to increase your comfort.

A number of factors may cause a muscle to cramp or spasm. The most common causes include:

  • inadequate blood flow to the muscle
  • muscle injuries
  • exercising in excessive heat or cold
  • overuse of a specific muscle during exercise
  • stress, most often in the neck muscles
  • not stretching before exercise
  • nerve compression in the spine
  • taking diuretics, which can lead to low potassium levels
  • mineral depletion, or having too little calcium, potassium, and sodium in the blood
  • dehydration

Many people experience charley horses during sleeping hours and are awakened because of them.

Muscle spasms that cause charley horses while you sleep are common. However, why these nighttime spams occur isn’t entirely understood. It’s believed that lying in bed in an awkward position for a long time plays a role.

Muscle spasms can happen to anyone, at any age. And a charley horse can occur at any time of the day or night.

Charley horses do tend to occur more often among people in the following groups:

  • athletes
  • infants
  • older adults
  • people who are obese
  • people taking certain medications like diuretics, raloxifene (Evista), or statin drugs
  • people who smoke

People who are obese are more likely to experience charley horses because of poor circulation in their legs. Athletes often experience charley horses because of muscle fatigue or overuse.

The occasional charley horse doesn’t require an official medical diagnosis. However, your doctor should investigate frequent, recurrent muscle spasms. This would apply if a charley horse occurs more than once a week without an adequate explanation.

Your doctor can usually make a diagnosis based on your medical history and a physical examination.

MRI scans may be helpful in determining whether nerve compression is the cause of frequent charley horses. An MRI machine uses a magnetic field and radio waves to create a detailed image of your body’s internal structures.

Laboratory work may also be needed to rule out low potassium, calcium, or magnesium levels.

You may be referred to a physical therapist or other specialist if your doctor suspects nerve damage or other complex causes.

The treatment for charley horses depends on the underlying cause. If a charley horse is exercise-induced, simple stretches and massages can help relax the muscle and stop it from contracting.

Heating pads can accelerate the relaxation process, while an ice pack can help numb the pain. If your muscle is still sore after a muscle spasm, your doctor may recommend a nonsteroidal anti-inflammatory medication like ibuprofen.

Recurrent charley horses require more aggressive treatment. Your doctor may prescribe pain medications if ibuprofen doesn’t help.

In severe cases, your doctor may prescribe antispasmodic medication. Also, physical therapy can help you cope with muscle spasms and prevent further complications.

In extreme cases, you doctor may recommend surgery. If other treatments fail, surgery can enlarge the space around a nerve to relieve pressure. This may help if nerve compression causes your spasms.

There are certain massages and stretches that can provide immediate relief and prevent potential pain when you experience a charley horse.

During a charley horse, you can use your hands to apply pressure to the site of the cramp to relieve pain. You can also try using both of your thumbs to gradually apply pressure to the site of the cramp until the pain goes away.

If your charley horse is in your leg, you can try to relieve the pain by doing the following stretches:

  • standing up
  • stepping the leg that isn’t experiencing muscle cramping forward into a lunge
  • straightening the back of the leg that is experiencing the cramp and lunging forward on the front leg

You can also stand on the tips of your toes for a few seconds to stretch your calf muscles.

Once you identify the cause of the occasional charley horse, symptoms are generally easy to prevent. Take these steps to help avoid future muscle spasms:

  • Stretch before and after exercise.
  • Avoid exercising the same muscles on consecutive days.
  • Do not exercise in severe weather.
  • Drink water throughout the day.
  • Drink beverages that contain electrolytes, such as Gatorade.
  • Stretch before going to bed.

Charley horses are common and can occur in any muscle at any time. They’re usually treatable and can sometimes be prevented.

Any pain caused by a spasm won’t typically last more than a day. However, if you experience charley horses frequently, talk with your doctor about treatments.

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