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acetaminophen, dextromethorphan, guaifenesin, phenylephrine (cont.)

What should I discuss with my healthcare provider before taking acetaminophen, dextromethorphan, guaifenesin, and phenylephrine?

Do not take this medication if you are allergic to acetaminophen, dextromethorphan, guaifenesin, or phenylephrine.

Do not use a cough and cold medicine if you have used an MAO inhibitor such as isocarboxazid (Marplan), phenelzine (Nardil), rasagiline (Azilect), selegiline (Eldepryl, Emsam), or tranylcypromine (Parnate) within the past 14 days. Serious, life-threatening side effects can occur if you take a cough and cold medicine before the MAO inhibitor has cleared from your body.

Ask a doctor or pharmacist if it is safe for you to take this medicine if you have:

This medication may be harmful to an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant during treatment.

This medication may pass into breast milk and could harm a nursing baby. Do not use this medication without telling your doctor if you are breast-feeding a baby.

Older adults may be more sensitive to the effects of this medication.

The liquid form of this medicine may contain sugar or phenylalanine. Talk to your doctor before using this form if you have diabetes or phenylketonuria (PKU).

How should I take acetaminophen, dextromethorphan, guaifenesin, and phenylephrine?

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. Cold medicine is usually taken only for a short time until your symptoms clear up.

An overdose of acetaminophen can damage your liver. Adults should not take more than 1 gram (1000 mg) of acetaminophen per dose or 4 grams (4000 mg) per day. Ask a doctor before taking acetaminophen if you drink more than 3 alcoholic beverages per day, and never take more than 2 grams (2000 mg) of acetaminophen per day.

One packet of the oral powder may contain up to 1000 mg of acetaminophen. Know the amount of acetaminophen in the specific product you are taking.

Do not give this medication to a child younger than 4 years old. Always ask a doctor before giving a cough or cold medicine to a child. Death can occur from the misuse of cough and cold medicines in very young children.

You may take this medicine with or without food.

Measure liquid medicine with a special dose-measuring spoon or cup, not a regular table spoon. If you do not have a dose-measuring device, ask your pharmacist for one.

Drink extra fluids to help loosen the congestion and lubricate your throat while you are taking this medication.

Talk with your doctor if your symptoms do not improve after a few days of using this medication, or if you have:

  • nervous feeling, dizziness, or trouble sleeping;
  • a severe sore throat lasting longer than 2 days;
  • pain, stuffy nose, or cough lasting longer than 7 days;
  • a fever with headache, nausea, vomiting, or skin rash;
  • redness or swelling; or
  • any other new or worsening symptoms.

This medication can cause unusual results with certain medical tests. Tell any doctor who treats you that you are taking this medicine.

If you need surgery, tell the surgeon ahead of time if you have taken a cold medicine within the past few days.

Store at room temperature, away from moisture, heat, and light.

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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