Guaifenesin: uses, dosing, side effects & brands
Guaifenesin is an expectorant sold in the U.S. under one brand, for bronchitis, common cold and cough. Below: what the FDA label says, every product that contains it, what the pills look like, and its recall record.
Key facts
- Drug class
- Expectorant
- Treats
- Bronchitis, Common Cold and Cough
- Available as
- Tablet, extended release
- Sold as
- Mucinex
- Prescription?
- Over the counter
- Generic available?
- Not in our catalog
- What the pharmacy pays
- about $0.07 per ml — not your price
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How guaifenesin is dosed
From the FDA label for Mucinex (application NDA021282). Other guaifenesin products — different forms, different strengths — are dosed differently. Follow the label for the one you were prescribed.
Directions do not crush, chew, or break tablet take with a full glass of water this product can be administered without regard for the timing of meals adults and children 12 years of age and over: 1 or 2 tablets every 12 hours. Do not exceed 4 tablets in 24 hours. children under 12 years of age: do not use
Can you take guaifenesin with…?
Source-cited answers for the combinations people actually ask about — each with a verdict and what to watch for.
Every guaifenesin product we track (1)
Same active ingredient — different manufacturer, form, price and FDA recall record. That last one is what our independent score measures.
Only one: Mucinex.
What guaifenesin pills look like
Imprint codes, colour and shape from the FDA’s labelling data. Match the imprint on your pill — or search any imprint.
Combination products containing guaifenesin
A combination is a different drug — different dosing, different warnings. It is listed here so you can find it, not so you can substitute it.
Guaifenesin recalls
From the FDA Enforcement database. A recall covers specific lots — not the drug as a whole.
Guaifenesin and Codeine Phosphate Oral Solution USP
Superpotent; sodium benzoate preservative
PAI Holdings, LLC. dba Pharmaceutical Associates Inc · Jan 7, 2025
Guaifenesin Dextromethorphan Syrup
Failed Impurity/Degradation Specifications
The Harvard Drug Group LLC dba Major Pharmaceuticals and Rugby Laboratories · Nov 7, 2024
Guaifenesin Dextromethorphan Syrup
Failed Impurity/Degradation Specifications
The Harvard Drug Group LLC dba Major Pharmaceuticals and Rugby Laboratories · Nov 7, 2024
How long guaifenesin keeps
No guaifenesin label we read sets a separate limit for after opening, but they do specify how it must be stored — and the stability behind any date assumes those conditions.
Does guaifenesin expire? The in-use limits and storage rules from its labelsGiving guaifenesin to a child
Children’s guaifenesin is sold at 28 different strengths, and each has its own dosing chart on its label — a chart is only correct for the bottle it was printed on. We hold the chart from 38 labelled products.
Children’s guaifenesin dosage charts, by strengthGuaifenesin and breastfeeding
From LactMed, the US National Library of Medicine’s Drugs and Lactation Database — quoted, not rewritten.
Full LactMed record for guaifenesin: levels in milk, effects in breastfed infants, and the drugs it would consider insteadNeither the excretion of guaifenesin in milk nor its effect on breastfed infants have been studied. It is unlikely that with usual maternal doses amounts in breastmilk would harm the nursing infant, especially in infants over 2 months of age. It is best to avoid the use of products with a high alcohol content while nursing.
National Institute of Child Health and Human Development, record revised April 15, 2026. LactMed states its information is not a substitute for professional judgement.
What people report to the FDA about guaifenesin
The FDA Adverse Event Reporting System (FAERS) collects reports from patients and clinicians. It holds 16,369 reports naming guaifenesin, and the FDA flagged 67% of those reports as serious. The effects reported most often — leaving out reports about overdose, misuse or the condition being treated, which dominate the raw list for common medicines:
- dyspnoea1,124 reports
- nausea1,046 reports
- fatigue986 reports
- pneumonia941 reports
- diarrhoea934 reports
- cough863 reports
- headache862 reports
- dizziness742 reports
Read these as a signal, not a rate. A report does not mean guaifenesin caused the effect — anyone can file one, and many describe people taking several medicines for several conditions. Crucially there is no denominator: FAERS does not record how many people took the drug, so these counts cannot be turned into “X% of patients” — a bigger number often just means a more widely used or more talked-about drug. Duplicates exist, and publicity drives reporting. For what is actually established, read the FDA label section above.
Source: openFDA drug/event (FAERS), retrieved July 25, 2026.
Related calculators
Frequently asked questions
What is guaifenesin?
Uses helps loosen phlegm (mucus) and thin bronchial secretions to rid the bronchial passageways of bothersome mucus and make coughs more productive
What kind of drug is guaifenesin?
The FDA classifies guaifenesin as an expectorant. If you are checking whether it is safe to combine with something else, the class is what matters — two drugs from the same class usually should not be stacked.
Can you take guaifenesin with other medicines?
It depends on the medicine. We check it against the FDA labels rather than guessing: our interaction checker searches each drug's own label for the other and quotes what it says, naming the section it came from. Run guaifenesin against whatever else you take — and remember that a label not naming a drug is not the same as that combination being safe.
What forms does guaifenesin come in?
Across the brands we track, guaifenesin is currently marketed as tablet, extended release, per the FDA's National Drug Code Directory. Each form is dosed differently — follow the label for the exact product you were prescribed.
Is there a generic guaifenesin?
We do not currently list a generic-labelled guaifenesin product. That does not always mean none exists — it means none appears under a generic name in the FDA data we track. Ask your pharmacist.
Has guaifenesin been recalled?
The FDA's Enforcement database lists 3 recall records whose product description mentions guaifenesin. The most recent: Guaifenesin and Codeine Phosphate Oral Solution USP (Jan 7, 2025). A recall applies to specific lots, not to the drug as a whole — check the record for the affected lot numbers.
What should I avoid while taking guaifenesin?
Other medicines: we hold source-cited interaction answers for Can you take Motrin and Mucinex together?, Can you take Claritin and Robitussin together?, Can you take Tylenol and Robitussin DM together? and Can you take ibuprofen and Mucinex DM together?. This is what the FDA label and our cited sources say — it is not a complete list. Your pharmacist can check your own combination.
Cite this page
- APA
- pharmaranks. (2026, July 24). Guaifenesin: uses, dosing, side effects & brands. https://pharmaranks.com/drugs/guaifenesin
- MLA
- “Guaifenesin: uses, dosing, side effects & brands.” pharmaranks, 24 July 2026, https://pharmaranks.com/drugs/guaifenesin.
We summarise public FDA and NIH sources — for a clinical claim, cite the primary source we link to as well.
Sources: FDA openFDA drug label, National Drug Code Directory, and Enforcement (recall) database. This page reproduces public FDA data and is not medical advice. Dosing is set by your prescriber.
Read the full FDA label for guaifenesin on DailyMed (NIH) ↗.