On this page · 9 sections
Analgesic combinations oral tablet (25 mg-580 mg)

Diphenhydramine and magnesium salicylate

Generic name: diphenhydramine and magnesium salicylate

Brand names: Doans PM

Last updated November 2, 2026 0 views
Share

What is diphenhydramine and magnesium salicylate?

Diphenhydramine is an antihistamine that is sometimes used to help with sleep. Magnesium salicylate is a nonsteroidal anti-inflammatory drug (NSAID) that belongs to a group of drugs called salicylates (sa-LIS-il-ates).

Diphenhydramine and magnesium salicylate is a combination medicine that is used to treat back pain that disrupts your normal sleep.

Diphenhydramine and magnesium salicylate may also be used for reasons not mentioned in this medication guide.

This section was rewritten for readability and reviewed for meaning.

How should I take diphenhydramine and magnesium salicylate?

Use exactly as directed on the label, or as prescribed by your doctor.

Taking too much diphenhydramine can lead to serious heart problems, seizures, coma, or death.

Take this medicine with a full glass of water before bedtime.

Take with food if this medicine upsets your stomach.

Do not use this medicine to make a child sleepy.

Stop taking this medicine and call your doctor if your pain does not improve, or if it gets worse after 10 days of using this medicine. Tell your doctor if you have a fever that lasts longer than 3 days, or if you have any redness or swelling.

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

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

Store at room temperature away from moisture and heat.

This section was rewritten for readability and reviewed for meaning.

Warnings

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

Magnesium salicylate may cause stomach or intestinal bleeding, which can be life-threatening. Call your doctor right away if you have symptoms of stomach bleeding like dizziness, black or bloody stools, or coughing up blood.

Ask a doctor before giving this medicine to a child younger than 12 years old. Do not give this medicine to a child or teenager who has a fever, flu symptoms, or chickenpox. Do not use this medicine to make a child sleepy.

This section was rewritten for readability and reviewed for meaning.

Before taking this medicine

You should not use diphenhydramine and magnesium salicylate if you are allergic to aspirin or other salicylates.

Do not give this medicine to a child or teenager with a fever, flu symptoms, or chickenpox. Salicylates can cause Reye's syndrome, a serious and sometimes fatal condition in children. Ask a doctor before giving the medicine to a child younger than 12 years old.

Magnesium salicylate may cause stomach or intestinal bleeding, which can be fatal. These conditions can happen unexpectedly while you are using magnesium salicylate, especially in older adults.

Ask a doctor or pharmacist if this medicine is safe to use if you have ever had:

  • bleeding problems;
  • heartburn, stomach ulcer, or stomach bleeding;
  • an enlarged prostate or urination problems;
  • asthma or COPD, cough with mucus, or cough caused by smoking, emphysema, or chronic bronchitis;
  • heart disease, high blood pressure;
  • liver disease, cirrhosis, or if you drink more than 3 alcoholic beverages per day;
  • kidney disease;
  • arthritis, gout;
  • diabetes;
  • glaucoma; or
  • a thyroid disorder.

Ask a doctor before using this medicine if you are pregnant or breastfeeding.

Taking this medicine during the last 20 weeks of pregnancy may cause serious kidney problems in the unborn baby, or bleeding in the mother or the baby during delivery.

This section was rewritten for readability and reviewed for meaning.

Diphenhydramine and magnesium salicylate side effects

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

diphenhydramine and magnesium salicylate may cause serious side effects. Stop using diphenhydramine and magnesium salicylate and call your doctor right away 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 of diphenhydramine and magnesium salicylate 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
  • daytime drowsiness or a "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. You may report side effects to the FDA at 1-800-FDA-1088.

This section was rewritten for readability and reviewed for meaning.

Diphenhydramine and magnesium salicylate dosing information

Usual Adult Dose for Insomnia:

Diphenhydramine-magnesium salicylate 25 mg-580 mg oral tablet:2 tablets orally at bedtime as needed with a full glass of water.

Usual Adult Dose for Pain:

Diphenhydramine-magnesium salicylate 25 mg-580 mg oral tablet:2 tablets orally at bedtime as needed with a full glass of water.

Usual Pediatric Dose for Insomnia:

Diphenhydramine-magnesium salicylate 25 mg-580 mg oral tablet:12 years or older: 2 tablets orally at bedtime as needed with a full glass of water.

Usual Pediatric Dose for Pain:

Diphenhydramine-magnesium salicylate 25 mg-580 mg oral tablet:12 years or older: 2 tablets orally at bedtime as needed with a full glass of water.

What happens if I miss a dose?

Since diphenhydramine and magnesium salicylate is taken as needed, you may not have a regular dosing schedule. If you miss a dose and it's nearly time for your next dose, just skip the missed dose. Do not take two doses at the same time.

This section was rewritten for readability and reviewed for meaning.

What happens if I overdose?

Seek emergency medical help or call the Poison Help line at 1-800-222-1222. Taking too much diphenhydramine can be deadly.

Signs of an overdose may include vomiting, confusion, extreme drowsiness, ringing in the ears, not being able to urinate, very dry eyes and mouth, dilated pupils, rapid heartbeats, tremors, agitation, hallucinations, or seizures.

Do not drive or participate in dangerous activities until you know how diphenhydramine and magnesium salicylate affect you. Your ability to react may be affected.

Also, talk to a doctor or pharmacist before using any other medicine that may have diphenhydramine or ingredients similar to magnesium salicylate (like aspirin or other salicylates). This includes medications for pain, fever, swelling, sleep, cold/allergy symptoms, or anti-itch creams. Taking too much diphenhydramine can lead to a fatal overdose.

Avoid alcohol. Drinking heavily can increase your chance of stomach bleeding.

This section was rewritten for readability and reviewed for meaning.

What other drugs will affect diphenhydramine and magnesium salicylate?

Ask a doctor or pharmacist before using this medicine with any other drugs that can cause drowsiness (such as opioid medication, sleep medicine, a muscle relaxer, or medicine for anxiety or seizures).

Ask a doctor or pharmacist if it is safe for you to use diphenhydramine and magnesium salicylate if you are also using:

  • a blood thinner--warfarin, Coumadin, Jantoven;
  • other NSAIDs (nonsteroidal anti-inflammatory drugs)--aspirin, ibuprofen (Advil, Motrin), naproxen (Aleve), celecoxib, diclofenac, indomethacin, meloxicam, and others;

This list is not complete. Other drugs may affect diphenhydramine and magnesium salicylate, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.

This section was rewritten for readability and reviewed for meaning.

Related medicines

Before you take this medicine: the information on this page is general and may not cover your personal circumstances. Read the label supplied with your medicine and ask a pharmacist or doctor if you are unsure, especially if you are pregnant, breastfeeding, taking other medicines or managing a long-term condition.
General medicine information Consumer-friendly language

Content is provided for education and is not medical advice. See our medical disclaimer.