What Is a Charley Horse?

Medically Reviewed by Zilpah Sheikh, MD on July 18, 2024
6 min read

A charley horse is a muscle spasm -- when a muscle suddenly tightens up on its own and can’t relax. These cramps can happen anywhere in your body. They’re common in your legs and feet.

A muscle cramp, though painful, is harmless and usually only lasts seconds to minutes. Often, you can take care of the pain yourself at home with a little stretching.

Though you might get a cramp because of exercise or other activities, it can just as easily happen when you’re sitting still or sleeping.

Things that can trigger a charley horse include:

  • Poor blood flow
  • Working your muscles too much
  • Not stretching enough
  • Being active in high or low temperatures
  • Dehydration
  • A lack of magnesium and/or potassium in your diet
  • Problems such as a spinal cord injury or a pinched nerve in your neck or back
  • Kidney disease
  • Getting dialysis, a treatment you get when you have kidney failure
  • Pregnancy
  • Stress
  • Poor posture
  • Muscle injury
  • Hyperexcitable nerves

Muscle cramps can also be a side effect of some drugs, such as:

  • Albuterol (Proventil, Ventolin) and terbutaline (Brethine) -- which are asthma medications
  • Donepezil (Aricept), used to treat Alzheimer's disease
  • Furosemide (Lasix), hydrochlorothiazide (Microzide), and other diuretics ("water pills") that lower the levels of certain electrolytes (sodium and potassium) and take fluid out of your body
  • Neostigmine (Prostigmine), used for myasthenia gravis
  • Nifedipine (Procardia), a treatment for angina and high blood pressure
  • Raloxifene (Evista), an osteoporosis treatment
  • Tolcapone (Tasmar), which treats Parkinson's disease
  • Statin medications for cholesterol, such as atorvastatin (Lipitor), fluvastatin (Lescol), lovastatin (Mevacor), pravastatin (Pravachol), rosuvastatin (Crestor), or simvastatin (Zocor)

Certain people tend to get charley horses more often, including:

  • Older adults
  • Athletes
  • Pregnant people
  • People who are overweight or obese
  • Those who have conditions such as diabetes or thyroid, liver, or nerve disorders

A charley horse feels like the affected muscle has tightened up and locked down. It’s painful and can happen suddenly – even when you’re just lying there, sleeping.

Leg cramps are usually nothing to worry about as they often go away on their own without any medicines. However, see a doctor if your leg cramps cause symptoms such as:

  • Serious pain and discomfort
  • Leg swelling and redness 
  • Skin changes
  • Muscle weakness

Also, see a doctor if you have leg cramps often that don’t go away with home remedies such as stretching. 

Having these symptoms with your leg cramps could be due to serious health conditions, including:

  • Kidney disease
  • Diabetes
  • Nerve damage in your legs
  • Spinal cord injury 
  • Vascular disorders
  • Thyroid disease
  • Liver disease

Your doctor can let you know why you might have persistent and serious leg cramps and recommend treatment.

You don’t need to see your doctor unless you have a charley horse along with one of these conditions:

  • Weakness
  • Numbness
  • Vomiting, diarrhea, or severe sweating (which can cause dehydration)

Your doctor will ask about your symptoms and medical history and do a physical exam. They might order blood tests, muscle tests, nerve conduction studies, electromyography (EMG), or MRI exams to look for a health condition that can cause cramps.

Stretching the affected area is often helpful. Here are some ways to do that for specific areas:

Charley horse in your calf or the back of your thigh (hamstring). Put your weight on the affected leg and bend your knee slightly. Or sit or lie down with your leg out straight and pull the top of your foot toward your head.

Cramp in the front of your thigh (quadriceps). Hold on to a chair and bend the knee of the affected leg. Pull your foot up toward your buttock.

Foot cramp treatment. When your foot muscle tightens up, try these tips to help it relax:

  • If you’re sitting or lying down, stand up and put weight on your cramping foot. Hold onto something if you feel like you might lose your balance.
  • Flex your foot and toes, lifting them upward toward your nose. (If standing, walk on your heels.) You can also stretch the muscles by grabbing your foot with your hand or wrapping a towel, necktie, or belt around the ball of your foot and toes, pulling the foot further up toward your nose.
  • Rub your muscles gently as you stretch them. Try icing the area while you massage it. Put ice cubes in a plastic bag or use an ice pack. Never put ice directly on your skin.
  • If ice is not working, put heat on the cramped muscle with a warm towel or heating pad. You can also soak it in warm water.

You can also take an over-the-counter pain reliever such as ibuprofen to help ease any remaining aches.

Massage, a bath with Epsom salts, or a heating pad can relax the muscles. To ease pain, use an ice pack or take an over-the-counter medication such as ibuprofen or naproxen.

Taking vitamin B12 complex, calcium, or magnesium supplements may help ease and prevent leg cramps, too. Talk to your doctor before you start taking any supplements.

In most cases, a charley horse will stop within a few minutes. But if you get them often and for no obvious reason, tell your doctor.

Your doctor may recommend medicines for your cramps if a medical condition is causing it. However, medicines recommended for leg cramps don’t always work and may cause side effects such as nausea, vomiting, and seizures. These medicines include:

  • Benzodiazepine, which makes the brain and nervous system less active
  • Carisoprodol, which helps relax your muscles
  • Diltiazem, often used to treat high blood pressure and chest pain
  • Gabapentin, a medication for seizures and nerve pain
  • Mexiletine, often prescribed for abnormal heart rhythms
  • Orphenadrine, which helps relax your muscles
  • Verapamil, which is used to manage high blood pressure and chest pain

To help stop cramps before they start:

  • Eat more foods high in vitamins and magnesium.
  • Stay hydrated.
  • Stretch daily, especially before exercise. Stretching before exercise can help prevent tight muscles. Daily stretching can help with cramps caused by other things.
  • Wear comfortable shoes.
  • Limit how much alcohol you drink.
  • Ramp up your exercise slowly rather than all at once.
  • Don’t exercise right after you eat.
  • Don’t smoke.

A charley horse or muscle cramp is painful but harmless, lasting seconds to minutes. It can happen on any part of your body, but you’ll often have it on your legs and feet. It might occur due to many reasons such as dehydration, exercising a muscle too much, lacking magnesium or potassium, not doing enough stretches, and more. Usually, you don’t need to take medicines for it. Stretching and other exercises you can do at home may help. But if the cramps don’t go away, happen often, or happen with other symptoms, see a doctor for treatment.

How can I relieve a charley horse?

You can relieve a charley horse by taking over-the-counter pain relief medications such as ibuprofen, doing stretches, having a massage, or using heating pads.

What is the difference between a cramp and a charley horse?

A cramp is often called a charley horse.

Why do charley horses happen while I’m sleeping?

You might have charley horses while sleeping if you sit for too long during the day, overwork your muscles, have poor posture, or have health conditions such as kidney failure.