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Guaifenesin, Potassium guaiacolsulfonate and Dextromethorphan oral

Important Note

The following information is intended to supplement, not substitute for, the expertise and judgment of your physician, pharmacist or other healthcare professional. It should not be construed to indicate that use of the drug is safe, appropriate, or effective for you. Consult your healthcare professional before using this drug.


(gweye-FEN-eh-sin/poh-TASS-ee-um GWEYE-uh-koll-SULL-fun-ate/dex-tr ow-meth-OR-fan)



Guaifenesin and potassium guaiacolsulfonate are expectorants which help to loosen mucus. Dextromethorphan is a cough suppressant. This combination of medicines is used to treat cough due to colds, flu, hay fever, asthma, and other respiratory illness (e.g., sinusitis, pharyngitis, bronchitis). Also, phlegm (lung secretions) may become less thick after using this medication along with fluids.

How To Use

Take this medication twice daily (12 hours apart); or as directed by your doctor. Take this medication with a full glass of water. Water will also help to break-up mucus and clear congestion. Do not take more than the recommended dose. It is best to swallow the medicine whole. Do not crush or chew this medication. Drink plenty of fluids while taking this medication, unless your doctor instructs you otherwise. Notify your doctor if your condition does not improve or worsens in 7 days.

Side Effects

Nausea, vomiting, stomach upset, drowsiness or dizziness may occur. If these effects persist or worsen, notify your doctor. Tell your doctor immediately if any of these unlikely but serious side effects occur: painful urination (with fever and chills), blood in urine. A serious allergic reaction to this drug is unlikely, but seek immediate medical attention if it occurs. Symptoms of a serious allergic reaction include: rash, itching, swelling, severe dizziness, trouble breathing. If you notice other side effects not listed above, contact your doctor or pharmacist.


Tell your doctor your medical history, including: allergies (especially drug allergies). This medication may make you dizzy or drowsy; use caution engaging in activities requiring alertness such as driving or using machinery. Limit alcoholic beverages. This medication should not be given to children under 6 years of age. Ask your doctor or pharmacist for more details. This combination of medications should be used only when clearly needed during pregnancy. Discuss the risks and benefits with your doctor. It is not known whether this combination of medications passes into breast milk. Because of the potential risk to the infant, breast-feeding while using this product is not recommended. Consult your doctor before breast-feeding.

Drug Interactions

This drug should not be used with the following medications because very serious interactions may occur: memantine, sibutramine. If you are currently using any of these medications, tell your doctor or pharmacist before starting guaifenesin/potassium guaiacolsulfonate/dextromethorphan. Before using this medication, tell your doctor or pharmacist of all prescription and nonprescription/herbal products you may use. Avoid taking MAO inhibitors (e.g., furazolidone, isocarboxazid, linezolid, moclobemide, phenelzine, procarbazine, selegiline, tranylcypromine) within 2 weeks before or after treatment with this medication. In some cases a serious, possibly fatal, drug interaction may occur. Also report drugs that cause drowsiness such as: medicine for sleep (e.g., sedatives), tranquilizers, anti-anxiety drugs (e.g., diazepam), narcotic pain relievers (e.g., codeine), psychiatric medicines (e.g., phenothiazines such as chlorpromazine, or tricyclics such as amitriptyline), anti-seizure drugs (e.g., carbamazepine), muscle relaxants, antihistamines that cause drowsiness (e.g., diphenhydramine). This product can affect the results of certain lab test. Make sure laboratory personnel and your doctors know you use this drug. Do not start or stop any medicine without doctor or pharmacist approval.


If overdose is suspected, contact your local poison control center or emergency room immediately. Symptoms of overdose may include hallucinations, seizures, severe dizziness, inability to urinate, rapid heartbeat, trouble breathing.


Do not share this product with others.

Missed Dose

If you miss a dose, use it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.


Store at room temperature between 59 and 86 degrees F (15-30 degrees C) away from light and moisture. Do not store in the bathroom. Keep all medicines away from children and pets.