MST

Generic name: magnesium salicylate [ mag-NEE-zee-um-sa-LIS-i-late ]
Brand names: Doans Pills Extra Strength, MST, Nuprin Backache
Drug class: Salicylates

Medically reviewed by Drugs.com on Nov 6, 2024. Written by Cerner Multum.

What is MST?

MST is a nonsteroidal anti-inflammatory drug (NSAID) in a group of drugs called salicylates (sa-LIS-il-ates).

MST is used to provide temporary relief from backache.

MST may also be used for purposes not listed in this medication guide.

MST side effects

Get emergency medical help if you have signs of an allergic reaction: sneezing, runny or stuffy nose; wheezing or trouble breathing; hives; swelling of your face, lips, tongue, or throat.

MST may cause serious side effects. Stop using MST and call your doctor at once if you have:

• new symptoms such as redness or swelling;

• ringing in your ears, hearing loss;

• a light-headed feeling, like you might pass out;

• new or worsening stomach pain; or

• bloody or tarry stools, coughing up blood or vomit that looks like coffee grounds.

Less serious side effects may be more likely, and you may have none at all.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Warnings

MST can increase your risk of fatal heart attack or stroke. Do not use this medicine just before or after heart bypass surgery (coronary artery bypass graft, or CABG). This medicine may also cause stomach or intestinal bleeding, which can be fatal.

Do not give this medicine to a child or teenager with a fever, flu symptoms, or chickenpox.

Before taking this medicine

MST can increase your risk of fatal heart attack or stroke, even if you don't have any risk factors. Do not use MST just before or after heart bypass surgery (coronary artery bypass graft, or CABG).

MST may also cause stomach or intestinal bleeding, which can be fatal. These conditions can occur without warning while you are using this medicine, especially in older adults.

You should not use this medicine if you are allergic to aspirin or other salicylates.

Ask a doctor before giving the medicine to a child younger than 12 years old. Do not give this medicine to a child or teenager with a fever, flu symptoms, or chickenpox. Salicylates can cause Reye's syndrome, a serious and sometimes fatal condition in children.

Ask a doctor or pharmacist if this medicine is safe to use if you have ever had:

• bleeding problems;

• heartburn, stomach ulcer, or stomach bleeding;

• asthma;

• heart disease, high blood pressure;

• liver disease, cirrhosis, or if you drink more than 3 alcoholic beverages per day;

• kidney disease;

• arthritis, gout; or

• diabetes.

Ask a doctor before using this medicine if you are pregnant or breastfeeding.

If you are pregnant, you should not take this medicine unless your doctor tells you to. Taking an NSAID during the last 20 weeks of pregnancy can cause serious heart or kidney problems in the unborn baby and possible complications with your pregnancy.

How should I take MST?

Use exactly as directed on the label, or as prescribed by your doctor.

Take this medicine with a full glass of water.

Take with food if this medicine upsets your stomach.

Call your doctor if your symptoms get worse or you still have pain after 10 days. Tell your doctor if you have a fever that lasts longer than 3 days, or if you have any redness or swelling.

If you need surgery or dental work, tell the surgeon or dentist ahead of time that you are using MST. You may need to stop using the medicine for a short time.

Store at room temperature away from moisture and heat.

Related/similar drugs

acetaminophen, prednisone, tramadol, cyclobenzaprine, naproxen, oxycodone, Tylenol, methylprednisolone, triamcinolone, dexamethasone

What happens if I miss a dose?

Since MST is used when needed, you may not be on a dosing schedule. Skip any missed dose if it's almost time for your next dose. Do not use two doses at one time.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222. An overdose of magnesium salicylate can be fatal.

What should I avoid while taking MST?

Avoid alcohol. Heavy drinking can increase your risk of stomach bleeding.

Ask a doctor or pharmacist before using other medicines for pain, fever, swelling, or cold/flu symptoms. They may contain ingredients similar to MST (such as aspirin, ibuprofen, ketoprofen, or naproxen).

What other drugs will affect MST?

Ask a doctor or pharmacist if it is safe for you to use MST if you are also using:

• medicine to treat gout or arthritis;

• insulin or oral diabetes medicine; or

• other NSAIDs (nonsteroidal anti-inflammatory drugs)--aspirin, ibuprofen (Advil, Motrin), naproxen (Aleve), celecoxib, diclofenac, indomethacin, meloxicam, and others;

• a blood thinner--warfarin, Coumadin, Jantoven;

This list is not complete. Other drugs may affect MST, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Medical Disclaimer

Copyright 1996-2024 Cerner Multum, Inc. Version: 6.02.