Skip to Content

The originating document has been archived. We cannot confirm the completeness, accuracy and currency of the content.

Magnesium salicylate/ phenyltoloxamine

Generic Name: magnesium salicylate/phenyltoloxamine (mag-NEE-shum sa-LIS-ah-late/fen-ill-tole-OX-a-meen)
Brand Name: Examples include Magsal and Myogesic

Magnesium salicylate/ phenyltoloxamine is used for:

Treating mild to moderate aches and pains associated with arthritis. It may also be used for other conditions as determined by your doctor.

Magnesium salicylate/phenyltoloxamine is a salicylate and antihistamine combination. It works by blocking substances in the body that cause fever, pain, and inflammation.

Do NOT use magnesium salicylate/ phenyltoloxamine if:

  • you are allergic to any ingredient in magnesium salicylate/phenyltoloxamine
  • you have had a severe allergic reaction (eg, severe rash, hives, breathing difficulties, dizziness) to aspirin, tartrazine, or a nonsteroidal anti-inflammatory drug (NSAID) (eg, celecoxib, ibuprofen, naproxen)
  • you have bleeding problems, such as hemophilia, von Willebrand disease, or low blood platelets
  • you have lung problems (asthma, emphysema, chronic obstructive pulmonary disease [COPD]), difficulty urinating due to an enlarged prostate, or glaucoma
  • you are a child or teenager with influenza (flu) or chickenpox
  • you are taking an anticoagulant (eg, warfarin), methotrexate, or sodium oxybate (GHB)

Contact your doctor or health care provider right away if any of these apply to you.

Before using magnesium salicylate/ phenyltoloxamine:

Some medical conditions may interact with magnesium salicylate/phenyltoloxamine. Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you:

  • if you are pregnant, planning to become pregnant, or are breast-feeding
  • if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement
  • if you have allergies to medicines, foods, or other substances
  • if you have bleeding problems, blood vessel problems in the brain, blockage of the stomach or bowel, chickenpox, flu, rheumatoid arthritis, Kawasaki syndrome, prostate problems, blockage of the bladder, or difficulty urinating
  • if you have a history of asthma, growths in the nose (nasal polyps), kidney or liver problems, stomach or peptic ulcers (bleeding ulcers), heartburn, upset stomach, stomach pain, or vitamin K deficiency

Some MEDICINES MAY INTERACT with magnesium salicylate/phenyltoloxamine. Tell your health care provider if you are taking any other medicines, especially any of the following:

  • Carbonic anhydrase inhibitors (eg, acetazolamide) because they may decrease magnesium salicylate/phenyltoloxamine's effectiveness
  • Anticoagulants (eg, warfarin ) or NSAIDs (eg, celecoxib, ibuprofen, naproxen) because the risk of their side effects, including the risk of bleeding, may be increased by magnesium salicylate/phenyltoloxamine
  • Insulin, isoniazid, oral hypoglycemics (eg, glyburide), orsodium oxybate (GHB) because the risk of their side effects may be increased by magnesium salicylate/phenyltoloxamine
  • Methotrexate or valproic acid because the risk of their side effects may be increased by magnesium salicylate/phenyltoloxamine
  • Angiotensin-converting enzyme inhibitors (eg, enalapril), probenecid, or sulfinpyrazone because their effectiveness may be decreased by magnesium salicylate/phenyltoloxamine

This may not be a complete list of all interactions that may occur. Ask your health care provider if magnesium salicylate/phenyltoloxamine may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.

How to use magnesium salicylate/ phenyltoloxamine:

Use magnesium salicylate/phenyltoloxamine as directed by your doctor. Check the label on the medicine for exact dosing instructions.

  • Take magnesium salicylate/phenyltoloxamine by mouth with or without food. If stomach upset occurs, take with food to reduce stomach irritation.
  • Take magnesium salicylate/phenyltoloxamine with a full glass of water (8 oz/240 mL). Do not lie down for 30 minutes after taking magnesium salicylate/phenyltoloxamine.
  • Use magnesium salicylate/phenyltoloxamine exactly as directed on the package, unless instructed differently by your doctor. If you are taking magnesium salicylate/phenyltoloxamine without a prescription, follow any warnings and precautions on the label.
  • If you miss a dose of magnesium salicylate/phenyltoloxamine and you are taking it regularly, take it as soon as possible. If it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not take 2 doses at once.

Ask your health care provider any questions you may have about how to use magnesium salicylate/phenyltoloxamine.

Important safety information:

  • Magnesium salicylate/phenyltoloxamine may cause drowsiness. These effects may be worse if you take it with alcohol or certain medicines. Use magnesium salicylate/phenyltoloxamine with caution. Do not drive or perform other possibly unsafe tasks until you know how you react to it.
  • Magnesium salicylate/phenyltoloxamine has a salicylate in it. Before you start any new medicine, check the label to see if it has a salicylate in it too. If it does or if you are not sure, check with your doctor or pharmacist.
  • Magnesium salicylate/phenyltoloxamine has a salicylate in it, which has been linked to a serious illness called Reye syndrome. Do not give magnesium salicylate/phenyltoloxamine to a child or teenager who has the flu, chickenpox, or a viral infection. Contact your doctor with any questions or concerns.
  • Do not drink alcohol or use medicines that may cause drowsiness (eg, sleep aids, muscle relaxers) while you are using magnesium salicylate/phenyltoloxamine; it may add to their effects. Ask your pharmacist if you have questions about which medicines may cause drowsiness.
  • Do NOT take more than the recommended dose or use for longer than prescribed without checking with your doctor.
  • If you are taking magnesium salicylate/phenyltoloxamine for pain or fever and your symptoms do not improve within 10 days or if they become worse, check with your doctor.
  • Serious stomach ulcers or bleeding can occur with the use of magnesium salicylate/phenyltoloxamine. Taking it in high doses or for a long time, smoking, or drinking alcohol increases the risk of these side effects. Taking magnesium salicylate/phenyltoloxamine with food will NOT reduce the risk of these effects. Contact your doctor or emergency room at once if you develop severe stomach or back pain; black, tarry stools; vomit that looks like blood or coffee grounds; or unusual weight gain or swelling.
  • Magnesium salicylate/phenyltoloxamine may reduce the number of clot-forming cells (platelets) in your blood. Avoid activities that may cause bruising or injury. Tell your doctor if you have unusual bruising or bleeding. Tell your doctor if you have dark, tarry, or bloody stools.
  • Tell your doctor or dentist that you take magnesium salicylate/phenyltoloxamine before you receive any medical or dental care, emergency care, or surgery.
  • Magnesium salicylate/phenyltoloxamine should not be used in CHILDREN younger than 6 years old; safety and effectiveness in these children have not been confirmed.
  • PREGNANCY and BREAST-FEEDING: Do not use magnesium salicylate/phenyltoloxamine during the last 3 months of pregnancy; it may cause harm to the fetus. If you think you may be pregnant, contact your doctor. You will need to discuss the benefits and risks of using magnesium salicylate/phenyltoloxamine while you are pregnant. Magnesium salicylate/phenyltoloxamine is found in breast milk. If you are or will be breast-feeding while you use magnesium salicylate/phenyltoloxamine, check with your doctor. Discuss any possible risks to your baby.

Possible side effects of magnesium salicylate/ phenyltoloxamine:

All medicines may cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome:

Drowsiness; dry mouth, nose, or throat; heartburn; nausea; thickening of mucus in the nose and throat; upset stomach.

Seek medical attention right away if any of these SEVERE side effects occur:

Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); bloody or black stools; confusion; dark urine or pale stools; decreased urination; diarrhea; difficulty swallowing; dizziness; hearing loss; hoarseness; persistent sore throat or other signs of infection; ringing in the ears; severe stomach pain; unusual bruising or bleeding; unusual tiredness; vomiting.

This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider. Call your doctor for medical advice about side effects. To report side effects to the appropriate agency, please read the Guide to Reporting Problems to FDA.

If OVERDOSE is suspected:

Contact 1-800-222-1222 (the American Association of Poison Control Centers), your local poison control center, or emergency room immediately. Symptoms may include abnormal behavior; dark urine; excessive sweating; extreme tiredness; fast or deep breathing; loss of consciousness; ringing in the ears; stomach pain; vomiting.

Proper storage of magnesium salicylate/phenyltoloxamine:

Store magnesium salicylate/phenyltoloxamine at room temperature, between 68 and 77 degrees F (20 and 25 degrees C). Store away from heat, moisture, and light. Do not store in the bathroom. Keep magnesium salicylate/phenyltoloxamine out of the reach of children and away from pets.

General information:

  • If you have any questions about magnesium salicylate/phenyltoloxamine, please talk with your doctor, pharmacist, or other health care provider.
  • Magnesium salicylate/phenyltoloxamine is to be used only by the patient for whom it is prescribed. Do not share it with other people.
  • If your symptoms do not improve or if they become worse, check with your doctor.
  • Check with your pharmacist about how to dispose of unused medicine.

This information should not be used to decide whether or not to take magnesium salicylate/phenyltoloxamine or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about magnesium salicylate/phenyltoloxamine. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to magnesium salicylate/phenyltoloxamine. This information is not specific medical advice and does not replace information you receive from your health care provider. You must talk with your healthcare provider for complete information about the risks and benefits of using magnesium salicylate/phenyltoloxamine.

Issue Date: June 3, 2015

Further information

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