Epsom salt is an ingredient used in a soak to treat minor aches and pains. It’s thought to soothe tired muscles and reduce swelling.

As a medication administered intravenously, it can stave off premature birth and alleviate seizures caused by several conditions, including magnesium deficiency, preeclampsia, and eclampsia.

The most popular use for Epsom salt is in baths.

While there isn’t strong, scientific evidence supporting its effectiveness, many people say they feel relief for multiple symptoms by soaking in an Epsom salt bath.

Let’s look at how you can use it.

Epsom salts dissolve in water. Enthusiasts believe this allows magnesium and sulfates to be readily absorbed into skin. Whether this is sufficient for various treatments or not, Epsom salt is considered safe. It’s also easy to use, easy to find, and inexpensive.

How to do it

There really is no downside to taking a warm bath, although it’s important to check with your doctor first if you have low blood pressure. This is because hot water can temporarily lower blood pressure.

The Mayo Clinic recommends adults use 2 cups of Epsom salt per gallon of warm water. More than that can make the water feel slippery. It may also be drying to your skin.

Lower concentrations you can try are:

  • 300 grams (1.5 cups) of Epsom salt to 1 gallon of water
  • 1 cup of Epsom salt to 1 gallon of water
  • 2 cups of Epsom salt added to your bathtub of water

Soak for at least 15 minutes. If you’re soaking in an Epsom salt bath for aches and pains, make sure not to use water that’s too hot. This might worsen instead of reduce swelling.

Other ways to use Epsom salt in a soak:

Shop for Epsom salts for your bath.

Many Epsom salt advocates believe the amount of magnesium able to enter the body through the skin is sufficient for reducing swelling and relieving aches. It’s also thought that Epsom salts are effective for soothing skin and reducing irritation and itching.

When used as a soak, Epsom salt is generally considered safe.

If you’ve never had an Epsom salt bath, consider testing a patch of skin with magnesium sulfate and water first.

Avoid submerging broken skin in an Epsom salt bath.

Stop use if you experience:

  • itchy skin
  • allergic reactions, like hives or rash
  • skin infection

A 2017 review of studies indicates that larger and more methodical studies on topical application of Epsom salt need to be done. One 2005 study found that magnesium salts can be effective for dry skin and for reducing inflammation. However, the study doesn’t include the number of study participants analyzed.

As a folk remedy, Epsom salt is used on a widespread basis to provide relief for a variety of conditions. These include:

  • itching caused by poison ivy
  • skin irritation and inflammation
  • sore feet
  • sore muscles
  • sprains
  • stiff joints
  • stress
  • sunburn

Doctors also administer it intravenously. It’s been shown to be effective for these uses:

  • control rapid heartbeat
  • relieve migraine headaches
  • postpone premature birth
  • prevent seizures caused by preeclampsia and eclampsia
  • reduce swelling in the brain
  • treat barium poisoning
  • treat muscle spasms and seizures caused by magnesium deficiency

It’s used orally to treat:

  • constipation
  • low magnesium levels in blood

There’s some evidence that magnesium taken orally has a positive effect for several conditions, including:

  • stroke
  • heart disease
  • diabetes

It is, however, also possible to take too much magnesium by mouth.

Always check with your doctor before using Epsom salt by mouth. Follow the package instructions exactly. Too much magnesium can cause an irregular heartbeat and low blood pressure.

Epsom salt’s chemical name is magnesium sulfate. One story about magnesium sulfate’s takes place in the Epsom region of England. During a drought in 1618, a local cow herder named Henry Wicker bent down to drink from a pool of water in Epsom Common. He found the water acidic and bitter.

As the water evaporated, Wicker noticed white residue left behind and realized after drinking the water that it had a laxative effect. Epsom’s salts became a sought-after cure for constipation for hundreds of years following this happenstance discovery.

In 1755, a British chemist and physicist named Joseph Black conducted experiments on the chemical properties of magnesium sulfate. He proposed that magnesium be classified as an element.

Magnesium is essential for every life form on the planet. In the human body, it’s necessary for muscle and nerve function and maintaining a healthy immune system. It’s also needed to maintain a regular heartbeat, sufficient blood glucose, and strong bones.

Epsom salt baths can be relaxing and soothing. The benefits of a soak in Epsom salt-treated water have not been proven scientifically yet, but many people swear by this folk remedy. There’s very little downside to using Epsom salts in a bath.

Baths in general can be meditative and are a great way to take a break from daily stressors. Epsom salt may help your bath become even more relaxing by soothing tired muscles and easing stress.

You can also try different types of soaks, such as oatmeal baths or plain old bubble baths, to see if you get the same results.

Healthline and our partners may receive a portion of revenues if you make a purchase using a link above.