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When do muscle spasms signal a more serious problem?

Woman stretching outdoors to prevent muscle cramps

Twitching and cramps can be annoying, and in some cases, they may signal other issues. Here’s what to do when muscles go haywire.

Jennifer Thomas

By Jennifer Thomas

We’ve all been there: You’re in a work meeting when out of nowhere your eyelid starts doing a crazy tap dance. Or you’re on a jog when your calf muscle seizes up. These muscle spasms (aka muscle cramps) are unexpected but also very common. And in most cases, they’re no big deal.

But regular spasms can also be a sign of a more serious problem, such as kidney disease or a nerve injury. (On medication for a chronic condition? Download our discount prescription coupon app for savings of up to 80%.)

Here’s what to know about muscle spasms and when they might signal a bigger issue.

What are muscle spasms — and why do they happen?

There are some muscles in the body that you can’t control. (Think of the muscles that line your heart or your stomach.) And then there are others, such as the muscles in your arms and legs, that you can. These are called voluntary muscles. They’re connected to your nervous system, which links those muscles to your brain.

A muscle spasm happens when a voluntary muscle suddenly tightens up all on its own. Spasms can last anywhere from a few seconds to 15 minutes or longer. They’re most common in the hands, feet, calves, thighs and back.

Some spasms can be a mere annoyance, while others can be very painful and noticeable. “Sometimes the twitches can be visible, and the muscle can feel harder to the touch,” says Christine Haines, MD. She’s an emergency room specialist at Lenox Hill Hospital in New York City.

Muscle spasms can happen to anyone, anytime, including when you’re asleep. While you can’t always prevent them, there are some common spasm causes that are easy enough to fix. They include:

  • Dehydration: This is the most common cause of muscle spasms, says Erin Manning, MD. She’s a neurologist at the Hospital for Special Surgery in New York City. Your muscles need water to function properly. And when you’re not getting enough fluids, it’s possible you’re not getting enough electrolytes. Electrolytes are minerals such as sodium, calcium and potassium that, among other things, regulate muscle contractions. Vigorous exercise or taking a diuretic (which causes you to pee more often) can also lower your electrolyte levels.
  • Muscle overuse: Exercising too hard too often or simply holding a muscle in the same position for a long time can cause muscle spasms. “Lifting something heavy without the proper technique can also make muscle spasms more likely,” Dr. Haines says.
  • Stress: When you’re stressed, your body releases hormones that can cause your muscles to tense. That can lead to spasms.

Recommended reading: Your guide to the diuretic diet.

What to do during a muscle spasm

You’re sleeping soundly and all of a sudden — boom — you’re hit with a painful cramp in your calf or foot. What do you do? Unfortunately, there’s no magic pill. But these steps can help ease that tense muscle.

  • Lengthen the muscle: “Try to stretch out the muscle that’s being affected to help stop it from getting worse,” Dr. Manning says.
  • Try some physical activity: You can stand up and walk around, or do smaller movements such as knee bends or ankle rolls.
  • Massage the area: Use your hands or a roller to apply pressure to the muscles.
  • Apply heat or ice: You can use an ice pack or heating pad, or even take a warm bath. (Bonus points for bubbles.)
  • Take an over-the-counter (OTC) pain reliever: Think ibuprofen (Advil®, Motrin®) or acetaminophen (Tylenol®). (Need to stock up? Find great prices on OTC pain products at the Optum Store.)

What if my muscle spasms keep coming back?

Muscle spasms are very normal and usually not a cause for concern. That’s especially true if you get them only every now and again and you have an idea why (for example, after a long walk in hot weather).

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There are times, though, when muscle spasms can be more worrisome, especially if they’re paired with symptoms such as:

  • Weakness in your hands or feet
  • Loss of bowel function
  • Inability to urinate
  • Loss of sensation in the groin or genital area
  • Walking or balance problems
  • Shooting pain in an arm or a leg

“These symptoms may indicate a more serious condition that relates to the spinal cord or severe damage to a spinal nerve,” Dr. Haines says. “It’s important to have these symptoms evaluated immediately to avoid permanent damage.”

Nerve damage known as neuropathy can result from an injury, diabetes or an autoimmune disease such as lupus or rheumatoid arthritis. When nerves become damaged, it can disrupt communication between the body and the brain and cause muscle spasms. Muscle spasms are also sometimes a symptom of ALS (Lou Gehrig’s disease), multiple sclerosis, kidney disease (which throws your electrolyte balance out of whack) or hypothyroidism.

While spasms “can be an early sign of a nerve or muscle disorder, they’re rarely the only symptom that someone would experience with one of these conditions,” Dr. Manning says. Meaning, if spasms are your only symptom, don’t immediately jump to bad conclusions.

When in doubt, talk to your doctor about your muscle spasms. Meanwhile, if you have severe pain or neurological issues with a spasm, you should go to the emergency department for an MRI, Dr. Haines says. There, they can check for possible damage to your spinal cord.

How to keep muscle spasms at bay

You can’t always stop a muscle spasm from happening. But these lifestyle habits may help, according to the Cleveland Clinic:

  • Stay physically active and up the intensity of your workouts gradually.
  •  Avoid exercising in hot weather.
  • Stretch on a regular basis, especially before bed, or before and after exercise.
  • Pick footwear that fits and supports proper posture.
  • Sip water throughout the day. Generally, women should aim for 11.5 cups of fluid a day and men 15.5 cups, with 20% coming from food.
  • Take any prescribed vitamins and medications.

If your muscle cramps often happen during or after intense exercise, consider sipping water with added electrolytes. A small study published in the Journal of the International Society of Sports Nutrition had men run downhill on a treadmill in a hot room for 40 to 60 minutes. The men who drank electrolyte-enhanced water had significantly less cramping than those who hydrated with plain water.

Instead of reaching for a sugary sports drink, try to find an electrolyte-only powder or drink. Make sure it includes minerals such as sodium, potassium, magnesium and chloride to help your muscles work at their best.

Muscle cramps are annoying. But a few healthy habits can cut your chances of a painful seize-up. And if you’re prescribed a muscle relaxant or any other medication, be sure to grab your free prescription discount card. Simply show it to your pharmacist at checkout — you could save up to 80%.


Additional sources
Background on muscle spasms: Cleveland Clinic
Study on electrolyte-enhanced water versus plain water for muscle cramps: Journal of the International Society of Sports Nutrition (2021). “Effect of oral rehydration solution versus spring water intake during exercise in the heat on muscle cramp susceptibility of young men”