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

Do not use magnesium salicylate just before or after heart bypass surgery (coronary artery bypass graft, or CABG). You should not use this medication if you are allergic to aspirin or to an NSAID (non-steroidal anti-inflammatory drug), or if you have recently used:

• cidofovir (Vistide); or
• ketorolac (Toradol).

Magnesium salicylate may cause life-threatening heart or circulation problems such as heart attack or stroke, especially if you use it long term.

Magnesium salicylate may also cause serious effects on the stomach or intestines, including bleeding or perforation (forming of a hole). These conditions can be fatal and can occur without warning while you are taking this medicine, especially in older adults.

Ask a doctor or pharmacist if it is safe for you to take this medicine if you have:

• kidney disease;
• asthma;
• heart disease, high blood pressure, congestive heart failure;
• a history of stroke or heart attack;
• a stomach ulcer or intestinal bleeding;
• a bleeding or blood clotting disorder;
• diabetes;
• swelling or fluid retention;
• anemia (a lack of red blood cells);
• liver disease;
• an enzyme deficiency called glucose-6-phosphate dehydrogenase deficiency (G6PD);
• nasal polyps; or
• if you are dehydrated.

FDA pregnancy category C. Magnesium salicylate may be harmful to an unborn baby if the mother takes the medication during the last 3 months of pregnancy. Do not take this medication without telling your doctor if you are pregnant or plan to become pregnant during treatment.

Magnesium salicylate can pass into breast milk and may harm a nursing baby. Do not use this medication without telling your doctor if you are breast-feeding a baby.

This medication should not be given to a child or teenager who has a fever, especially if the child also has flu symptoms or chicken pox. Salicylates can cause a serious and sometimes fatal condition called Reye's syndrome in children.

Older adults may be more likely to have side effects from magnesium salicylate.

How should I take magnesium salicylate (MST, Nuprin Backache Caplet)?

Take exactly as prescribed by your doctor. Do not take in larger or smaller amounts or for longer than recommended. Follow the directions on your prescription label.

Magnesium salicylate may be taken up to 4 times per day. Follow your doctor's instructions.

Take the medicine with a full glass of water.

Take magnesium salicylate with food, milk, or an antacid if it upsets your stomach. To prevent stomach upset, do not lie down for at least 30 minutes after taking the medication.

It may take up to 2 weeks before your symptoms improve. Keep using the medication as directed and tell your doctor if your symptoms do not improve after 2 weeks of treatment.

This medication can cause unusual results with certain medical tests. Tell any doctor who treats you that you are using magnesium salicylate.

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.

Store at room temperature away from moisture and heat.

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