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Preserving Therapeutic Benefits: How Long Does Epsom Salt Last?

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Are you looking for an easy (and relaxing) way to get rid of that stress monkey off your back?

In that case, we suggest you treat yourself with an Epsom salt detox.

Over the years, Epsom salt has found massive acceptance due to its unique way of treating minor aches and pains. Sprinkle it on your hot bath, and boom! You find yourself swaying on the pain-free train.

So, what exactly is Epsom salt, and how does it work as a pain-relief agent?

Despite its name, Epsom salt is not the same as the traditional table salt, except for its chemical structure. Instead, it is a magnesium sulfate consisting of magnesium, oxygen, and sulfur.

It looks similar to table salt and dissolves when you put it in your hot bath. The dissolved compound (supposedly) comes in contact with your skin and helps treat various ailments.

However, that begs the question: how long does Epsom salt last? Will they become ineffective once they expire?

You will get all the answers here today!

How Long Does Epsom Salt Last? Does Epsom Salt Go Bad?

If you’re wondering if Epsom salt will go bad, the straightforward answer is yes!

However, you should know ‘going bad’ does not mean they expire or cause any harm to your body. Instead, they may slightly lose their efficacy.

The easiest way to know how long an Epsom salt will last is to look at its expiration date. The expected expiry date is usually 2-3 years post its manufacturing date.

However, you can use Epsom salt beyond that specified duration if you store them in proper conditions. The reason it lasts long is due to its chemical composition.

Magnesium Sulfate does not breakdown as easily as other compounds. As such, if you store them in a cool and dry place, they will last you several years even after its expiry date.

In some cases, if you have kept the container open for too long, it may get contaminated with moisture.

In such a case, you may notice the Epsom salt getting hard. But, you can easily break or dissolve them and use them as usual.

To put it in a nutshell, it is relatively hard for Epsom salt to grow microbes or other bacteria, at least, not if you keep them in a cool and dry place.

In any case, Epsom will remain safe to use. This is mainly because you only use them externally as a bathing agent.

So, even if they lose their potency, it does not cause any adverse health concerns.

The key to ensuring long shelf life is proper storage. The ideal way to preserve its efficacy is to keep it in an airtight container.

After that, you may want to store it in a cool and dry place away from water and sunlight.

How to Tell if Epsom Salt is Bad?

Even though Epsom remains good to use even after a year or two of its (supposed) expiry date, it is always a safer option if to check whether they have gone rancid or not.

Unlike other products, Epsom salt does not have a very noticeable telltale sign. They are present nonetheless.

The best way to know if they have gone wrong is to examine their appearance. If you notice it has started to become hard and clumpy, it is a good indication of moisture exposure.

Of course, you can still use them. But, if you fancy taking a hot bath filled with potent stress-relieving bubbles, we suggest you use a new pack.

Simply put, moisture is the enemy. As long as you can avoid such contamination, you will be able to enjoy an Epsom salt bath without any problems.

However, if you use Epsom salt as a laxative, you may want to take extra precautions. That is because a bad laxative Epsom salt can have some side effects.

Professionals recommend seeking a medical help if you experience signs of allergic reactions like swelling of tongue, face, and throat.

You may also experience difficulty in breathing and diarrhea. As a result, you may want to steer clear of an expired Epsom salt pill.  


Epsom salt is a life-saving solution for many people dealing with a multitude of minor health issues. People use it primarily to help them find relief from muscle aches, skin irritation/ inflammation, constipation, and stress relief.

Apart from that, people also widely use it as a foot soak to help them find relief from the athlete’s foot, toenail fungus and eliminate foot odor.

The best thing, however, is that Epsom salts do not expire like your regular table salt. Due to their extremely stable chemical composition, it is relatively difficult for them to go rancid.

Of course, proper storage also plays a big role. But, even under room temperature conditions, they should last you well for at least a year.

The key is to avoid moisture contamination. If you can do that, you should not have any issues whatsoever.

How Long Does Epsom Salt Last? Does Epsom Salt Go Bad?

Recipe by Kimberly Baxter Course: Shelf Life


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  • Epsom salt

  • Air-tight containers or Ziplock bags

  • Labels and markers


  • Read the guide thoroughly to learn how long it lasts.
  • Check the “Best-by-date” to know when it expires.
  • Make sure to store in an airtight container in a cool, dark place (pantry or fridge).
  • Always check for signs of spoilage before using.

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