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Diphenhydramine / magnesium salicylate Side Effects

Applies to diphenhydramine / magnesium salicylate: oral tablet


Use this medicine exactly as directed. Taking too much diphenhydramine can lead to serious heart problems, seizures, coma, or death.

Magnesium salicylate may cause stomach or intestinal bleeding, which can be fatal. Call your doctor at once if you have symptoms of stomach bleeding such as dizziness, black or bloody stools, or coughing up blood.

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. Do not use this medicine to make a child sleepy.

Get emergency medical help if you have signs of an allergic reaction: hives; wheezing, difficult breathing; feeling light-headed; swelling of your face, lips, tongue, or throat.

Stop using this medicine and call your doctor at once if you have:

  • severe drowsiness;

  • painful or difficult urination;

  • ringing in your ears, hearing loss;

  • confusion; 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.

Common side effects may include:

  • drowsiness;

  • dry eyes, blurred vision;

  • dry mouth, nose, or throat;

  • decreased urination;

  • heartburn, nausea, vomiting, gas;

  • constipation;

  • feeling restless or excited (especially in children); or

  • day-time drowsiness or "hangover" feeling after night-time use.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects.

More about diphenhydramine / magnesium salicylate

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

Some side effects may not be reported. You may report them to the FDA.