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Medications and Drugs

Brand Names: Doans PM

Generic Name: diphenhydramine and magnesium salicylate (Pronunciation: DYE fen HYE dra meen and mag NEE ze um sa LIS a late)

What is diphenhydramine and magnesium salicylate (Doans PM)?

Diphenhydramine is an antihistamine that reduces the natural chemical histamine in the body. It is often used as a sleep aid due to its common side effect of drowsiness.

Magnesium salicylate is in a class of drugs called salicylates (sa-LIS-il-ates). It works by reducing substances in the body that cause pain and inflammation.

The combination of diphenhydramine and magnesium salicylate is used to treat back pain that keeps you awake during your normal sleeping hours.

Diphenhydramine and magnesium salicylate may also be used for other purposes not listed in this medication guide.

What are the possible side effects of diphenhydramine and magnesium salicylate (Doans PM)?

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Stop using this medication and call your doctor at once if you have any of these serious side effects:

  • black, bloody, or tarry stools;
  • coughing up blood or vomit that looks like coffee grounds;
  • decreased hearing;
  • wheezing or trouble breathing;
  • seizure (convulsions);
  • urinating less than usual or not at all; or
  • nausea, stomach pain, low fever, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes).

Less serious side effects may include:

This is not a complete list of side effects and others may occur. Tell your doctor about any unusual or bothersome side effect. You may report side effects to FDA at 1-800-FDA-1088.

What is the most important information I should know about diphenhydramine and magnesium salicylate (Doans PM)?

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. Magnesium salicylate can cause a serious and sometimes fatal condition called Reye's syndrome in children.

You should not use this medication if you are allergic to diphenhydramine or magnesium salicylate.

Before taking this medication, tell your doctor if you have a breathing disorder, heart disease, high blood pressure, kidney or liver disease, diabetes, a thyroid disorder, glaucoma, stomach ulcer, hemophilia or other bleeding disorder, anemia, gout, enlarged prostate, urination problems, nasal polyps, or an allergy to an NSAID (non-steroidal anti-inflammatory drug) such as Advil, Motrin, Aleve, Indocin, Relafen, Feldene, and others.

Drinking alcohol may increase your risk of stomach bleeding while taking magnesium salicylate.

This medication can cause side effects that may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be awake and alert.

Do not use an over-the-counter cough, cold, allergy, or sleep medication without first asking your doctor or pharmacist. Read the label of any other medicine you are using to see if it contains diphenhydramine or another antihistamine.

There are many other medicines that can interact with diphenhydramine and magnesium salicylate. Tell your doctor about all the prescription and over-the-counter medications you use. This includes vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start using a new medication without telling your doctor. Keep a list with you of all the medicines you use and show this list to any doctor or other healthcare provider who treats you.

Report Problems to the Food and Drug Administration

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.

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