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Doans PM

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

Medically reviewed on April 13, 2018

What is Doans PM?

Diphenhydramine is an antihistamine that reduces the effects of natural chemical histamine in the body. Histamine can produce symptoms of sneezing, itching, watery eyes, and runny nose.

Magnesium salicylate is a nonsteroidal anti-inflammatory drug (NSAID) in a group of drugs called salicylates (sa-LIS-il-ates). This medicine works by reducing substances in the body that cause pain, fever, and inflammation.

Doans PM is a combination medicine used to treat back pain that keeps you awake during your normal sleeping hours.

This medicine may also be used for purposes not listed in this medication guide.

Important Information

Call your doctor at once if you have symptoms of stomach bleeding such as black, bloody, or tarry stools, or coughing up blood or vomit that looks like coffee grounds.

Do not give this medication 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.

Before taking this medicine

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

This medicine may also cause stomach or intestinal bleeding, which can be fatal. These conditions can occur without warning while you are taking this medicine.

Do not give this medication 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.

To make sure this medicine is safe for you, tell your doctor if you have:

It is not known whether this medicine will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant while using this medication. Taking a salicylate during late pregnancy may cause bleeding in the mother or the baby during delivery.

It is not known whether this medicine passes into breast milk or if it could harm a nursing baby. Tell your doctor if you are breast-feeding a baby.

Older adults may be more likely to have side effects from this medication.

How should I take Doans PM?

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 Doans PM before bedtime. Avoid lying down for at least 15 minutes after taking the medicine.

Take with food if this medicine upsets your stomach.

Call your doctor if your symptoms do not improve, or if they get worse after 10 days of using this medicine. Tell your doctor if you have a fever that lasts longer than 3 days.

If you need surgery or dental work, tell the surgeon or dentist ahead of time that you are using Doans PM. You may need to stop using the medicine for a short time.

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

Store at room temperature, away from moisture and heat.

What happens if I miss a dose?

Since this medication is usually taken only at bedtime as needed, you may not be on a dosing schedule. Take Doans PM only when you are ready for sleep. Do not take extra medicine to make up a missed dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while taking Doans PM?

Many medicines available over the counter also contain antihistamines (diphenhydramine and others) and salicylates or similar medicines (aspirin, ibuprofen, ketoprofen, naproxen). Ask your doctor before using cold or allergy medicine, over-the-counter sleep medicine, or any other medication for pain, arthritis, fever, or swelling.

Avoid drinking alcohol. It may increase your risk of stomach bleeding.

Avoid smoking, since it can also increase your risk of stomach irritation while taking Doans PM.

Doans PM side effects

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

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

  • pale skin, feeling tired or short of breath, unusual weakness;

  • confusion, ringing in your ears;

  • pain when swallowing;

  • little or no urinating; or

  • symptoms of stomach bleeding--dizziness, fainting, black, bloody, or tarry stools, or coughing up blood or vomit that looks like coffee grounds.

Common side effects may include:

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.

See also: Side effects (in more detail)

What other drugs will affect Doans PM?

Taking Doans PM with other drugs that make you sleepy or slow your breathing can worsen these effects. Ask your doctor before taking Doans PM with a sleeping pill, narcotic pain medicine, muscle relaxer, or medicine for anxiety, depression, or seizures.

Tell your doctor about all medicines you use, and those you start or stop using during your treatment with this medicine, especially:

  • cidofovir;

  • glaucoma medication;

  • gout medication;

  • methotrexate; or

  • other medicine that contains diphenhydramine.

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

Further information

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.

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

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