HOW TO USE: Take this medication twice daily (12 hours apart); or as directed by your doctor. Do not take more than the recommended dose. It is best to swallow the medicine whole. Do not crush or chew this medication. Take this medication with a full glass of water. The water also helps break up mucus and clear congestion. 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.

PRECAUTIONS: 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, and 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.

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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