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MST

Generic Name: magnesium salicylate (mag NEE zee um sa LIS i late)
Brand Name: Doans Pills Extra Strength, MST, Nuprin Backache

What is MST (magnesium salicylate)?

Magnesium salicylate is a salicylate (sa-LIS-il-ate). It works by reducing substances in the body that cause pain, fever, and inflammation.

Magnesium salicylate is used to treat mild-to-moderate pain, fever, inflammatory conditions, and pain, swelling, or stiffness associated with arthritis.

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

What is the most important information I should know about MST (magnesium salicylate)?

Do not take more of this medicine than recommended on the label. An overdose of magnesium salicylate can be fatal.

You should not use this medicine if you are allergic to salicylates (such as aspirin) or other nonsteroidal anti-inflammatory drugs (NSAIDs).

Magnesium salicylate may cause stomach or intestinal bleeding, which can be fatal. These conditions can occur without warning while you are using magnesium salicylate, especially in older adults.

Do not give this medicine to a child or teenager with a fever, flu symptoms, or chicken pox. Salicylates can cause Reye's syndrome, a serious and sometimes fatal condition in children.

What should I discuss with my healthcare provider before taking MST (magnesium salicylate)?

You should not use magnesium salicylate if you are allergic to it, or if you have ever had:

  • a severe allergic reaction after taking aspirin or an NSAID (non-steroidal anti-inflammatory drug) such as Advil, Motrin, Aleve, Orudis, Indocin, Lodine, Voltaren, Toradol, Mobic, Relafen, Feldene, and others.

Do not give this medicine to a child or teenager with a fever, flu symptoms, or chicken pox. Magnesium salicylate can cause Reye's syndrome, a serious and sometimes fatal condition in children. Magnesium salicylate is not approved for use by anyone younger than 12 years old.

To make sure magnesium salicylate is safe for you, tell your doctor if you have ever had:

  • stomach ulcer or bleeding;

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

  • kidney disease;

  • diabetes;

  • heart disease, high blood pressure; or

  • asthma.

Taking magnesium salicylate during late pregnancy may cause bleeding in the mother or the baby during delivery. Tell your doctor if you are pregnant or plan to become pregnant.

Magnesium salicylate can pass into breast milk and may harm a nursing baby. You should not breast-feed while using this medicine.

How should I take MST (magnesium salicylate)?

Use exactly as directed on the label, or as prescribed by your doctor. Do not use in larger or smaller amounts or for longer than recommended.

Take this medicine with a full glass of water.

Take with food if magnesium salicylate upsets your stomach.

If you need surgery, tell the surgeon ahead of time that you are using magnesium salicylate. You may need to stop using the medicine for a short time.

Call your doctor if your symptoms do not improve, or if you have a fever lasting longer than 3 days or pain lasting longer than 10 days.

Store at room temperature away from moisture and heat.

What happens if I miss a dose?

Since magnesium salicylate is used when needed, you may not be on a dosing schedule. If you are on a schedule, use the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not use extra medicine to make up the missed dose.

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.

Overdose symptoms may include nausea, vomiting, sweating more than usual, ringing in your ears, spinning sensation.

What should I avoid while taking MST (magnesium salicylate)?

Avoid drinking alcohol while you are taking magnesium salicylate. Alcohol may increase your risk of stomach bleeding.

Ask a doctor or pharmacist before using any cold, allergy, or pain medication. Many medicines available over the counter contain aspirin or other medicines similar to magnesium salicylate. Taking certain products together can cause you to get too much of this type of medication. Check the label to see if a medicine contains aspirin, ibuprofen, ketoprofen, or naproxen.

MST (magnesium salicylate) side effects

Get emergency medical help if you have signs of an allergic reaction: hives; pale or clammy skin; rapid heartbeats; dilated pupils; unexplained weakness or dizziness; fainting; difficult breathing, wheezing; swelling of your face, lips, tongue, or throat.

Stop using magnesium salicylate and call your doctor at once if you have:

  • redness or swelling;

  • ringing in your ears, hearing loss;

  • behavior changes with nausea and vomiting in a child using this medicine;

  • worsening fever or pain; or

  • signs of stomach bleeding--feeling light-headed, ongoing stomach pain, bloody or tarry stools, coughing up blood or vomit that looks like coffee grounds.

Side effects may be more likely in older adults.

Common side effects may include:

  • upset stomach; or

  • headache.

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.

Side Effects (complete list)

What other drugs will affect MST (magnesium salicylate)?

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

  • insulin or oral diabetes medicine;

  • gout medicine;

  • a steroid medicine;

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

  • a blood thinner--warfarin, Coumadin, Jantoven, and others.

This list is not complete. Other drugs may interact with magnesium salicylate, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed in this medication guide.

Where can I get more information?

  • Your pharmacist can provide more information about magnesium salicylate.
  • 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.
  • Disclaimer: Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.

Copyright 1996-2012 Cerner Multum, Inc. Version: 6.01.

Last reviewed: September 20, 2017
Date modified: December 03, 2017

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