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Dytan-DM Side Effects

Generic Name: dextromethorphan / diphenhydramine / phenylephrine

Note: This document contains side effect information about dextromethorphan / diphenhydramine / phenylephrine. Some of the dosage forms listed on this page may not apply to the brand name Dytan-DM.

Applies to dextromethorphan / diphenhydramine / phenylephrine: oral liquid, oral suspension extended release

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

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

  • confusion, severe anxiety, hallucinations, tremors;

  • weak or shallow breathing;

  • a light-headed feeling, like you might pass out;

  • fast or pounding heartbeats;

  • painful or difficult urination, little or no urinating;

  • pale skin, weakness, easy bruising or bleeding, fever, chills, body aches; or

  • increased blood pressure--severe headache, buzzing in your ears, chest pain, shortness of breath, uneven heartbeats.

Common side effects may include:

  • dizziness, drowsiness, headache;

  • constipation, upset stomach, loss of appetite;

  • blurred vision, double vision, dry eyes;

  • sleep problems (insomnia); or

  • dry mouth, nose, or throat.

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

Further information

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.

More about Dytan-DM (dextromethorphan / diphenhydramine / phenylephrine)

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