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Guaifenesin; Phenylephrine oral drops

What is this medication?

GUAIFENESIN; PHENYLEPHRINE (gwye FEN e sin; fen il EF rin) is a decongestant, expectorant combination. It is used to provide relief from cough and congestion. This medicine will not treat an infection.

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This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions.

COMMON BRAND NAME(S): Donatussin, Numonyl, Zoden

What should I tell my care team before I take this medication?

They need to know if you have any of the following conditions:

•blood vessel disease

•diabetes

•fever

•glaucoma

•heart disease or heart rhythm problems

•high blood pressure

•other chronic disease

•prostate trouble

•taken an MAOI like Carbex, Eldepryl, Marplan, Nardil, or Parnate within the last 14 days

•thyroid disease

•an unusual or allergic reaction to guaifenesin, phenylephrine, other medicines, foods, dyes, or preservatives

•pregnant or trying to get pregnant

•breast-feeding

How should I use this medication?

Take this medicine by mouth with a full glass of water. Follow the directions on the prescription label. Use a specially marked spoon or container to measure each dose. Ask your pharmacist if you do not have one. Household spoons are not accurate. Take your medicine at regular intervals. Do not take it more medicine than directed.

Talk to your pediatrician regarding the use of this medicine in children. While this drug may be prescribed for children as young as 2 years old for selected conditions, precautions do apply.

Patients over 65 years old may have a stronger reaction to this medicine and need smaller doses.

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Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once.

NOTE: This medicine is only for you. Do not share this medicine with others.

What if I miss a dose?

If you miss a dose, take it as soon as you can. If it is almost time for your next dose, take only that dose. Do not take double or extra doses.

What may interact with this medication?

Do not take this medicine with any of the following medications:

•bromocriptine

•ergot alkaloids like dihydroergotamine, ergonovine, ergotamine, methylergonovine

•MAOIs like Carbex, Eldepryl, Marplan, Nardil, and Parnate

•procarbazine

•stimulant medicines for attention disorders, weight loss, or to stay awake

This medicine may also interact with the following medications:

•indomethacin

•mecamylamine

•medicines for chest pain, heart disease, high blood pressure, or heart rhythm problems

•medicines for depression, anxiety, or psychotic disturbances

•methyldopa

•other medicines for allergies or colds

•reserpine

•some medicines used during surgery

This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.

What should I watch for while using this medication?

Tell your doctor or health care professional if your symptoms do not start to get better within 5 days or if they get worse. If you have trouble falling asleep at night, take the last dose of the day at least a few hours before bedtime.

Drink 6 to 8 glasses water daily while you are taking this medicine to help loosen mucus.

What side effects may I notice from receiving this medication?

Side effects that you should report to your doctor or health care professional as soon as possible:

•allergic reactions like skin rash, itching or hives, swelling of the face, lips, or tongue

•breathing problems

•confusion

•fast, irregular heartbeat

•hallucinations

•high blood pressure

•seizure

•tremor

•trouble passing urine

Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):

•anxiety, excitement, irritability, or nervousness

•diarrhea

•dizziness

•headache

•loss of appetite

•stomach upset, nausea

This list may not describe all possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Where should I keep my medication?

Keep out of the reach of children.

Store at room temperature between 15 and 30 degrees C (59 and 86 degrees F). Throw away any unused medicine after the expiration date.

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NOTE: This sheet is a summary. It may not cover all possible information. If you have questions about this medicine, talk to your doctor, pharmacist, or health care provider.

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Note: Introduction and Additional Common Questions written and medically approved by Cleveland Clinic professionals.

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