OTCs Today

Mary Warner

Colds and flu often result in chest congestion that can persist long after other symptoms have disappeared. An expectorant like guaifenesin can help thin mucus and phlegm and make it easier to cough up.

Guaifenesin (glyceryl guaiacolate) is the only FDA-approved expectorant for symptomatic relief of acute, ineffective cough. It works by loosening and thinning lower respiratory tract mucus and phlegm, making coughs more productive. It’s not intended to treat chronic cough associated with chronic lower respiratory tract diseases such as asthma, COPD, or emphysema, or for smoker’s cough. Guaifenesin may help control symptoms but does not treat the cause of symptoms or speed recovery.

Availability, dosage, and safety

Guaifenesin is available as tablets, capsules, extended-release tablets, dissolving granules, and liquids. Alcohol-, sucrose-, and dye-free formulations are also available.

As with all nonprescription cough and cold combination products, products that contain guaifenesin can cause serious adverse effects or death in young children. FDA-approved dosages of guaifenesin are 200 mg to 400 mg every 4 hours as needed for adults and children 12 years or older, 200 mg to 400 mg every 4 hours as needed for children aged 6 years to 12 years, and 50 mg to 100 mg every 4 hours as needed for children aged 2 years to 6 years. Guaifenesin is not FDA-approved for children younger than 2 years old.

Guaifenesin is often combined with antihistamines, cough suppressants, and decongestants, so it’s important to carefully check the labels of any other nonprescription medications used at the same time to ensure that no more than the recommended dosage of guaifenesin is delivered. Products intended for adults should not be given to children.

Guaifenesin is generally well-tolerated, though adverse effects can include nausea, vomiting, dizziness, headache, rash, diarrhea, drowsiness, and stomach pain. Most reports of guaifenesin overdose involve combinations of medications and are difficult to assess. However, signs and symptoms of overdose appear to be extensions of guaifenesin’s adverse effects.

What to tell your patients

Advise patients to drink plenty of water while taking guaifenesin and to continue their normal diet. Ensure that they understand that guaifenesin and other expectorants work best during the daytime since they will cause patients to cough more to clear congestion from the respiratory tract. Advise patients to see their primary care provider if their cough has not improved after 7 days or if they have a fever, skin rash, continuing headache, or sore throat with the cough.

For further information, please see APhA’s Handbook of Nonprescription Drugs, available for purchase on pharmacist.com or in Pharmacy Library. ■

Examples of nonprescription medications that contain guaifenesin

Single ingredient products

• Adult Tussin®
• Air-Power®
• Bronchoril®
• Siltussin DAS®
• Siltussin SA®
• Topcare Mucus Relief®
• Topcare Tussin®
• Childrens Mucus Relief®
• Little Remedies Little Colds Mucus Relief Expectorant Melt Aways®
• Mucinex®
• Mucinex Childrens®
• Mucinex for Kids®
• Mucus Relief®
• Q-Tussin®
• Robitussin® Chest Congestion
• Scot-Tussin® Expectorant SF Cough
• Tussin®
• Up and Up Childrens Mucus Relief®
• Vicks® DayQuil®

Combination products

• Adult Tussin DM® (dextromethorphan, guaifenesin)
• Aldex® (guaifenesin, pseudoephedrine)
• Biocotron® (dextromethorphan, guaifenesin)
• Biospec® (dextromethorphan, guaifenesin)
• Childrens Mucus Relief® (dextromethorphan, guaifenesin)
• Chlo Tuss® (chlophedianol, guaifenesin)
• Codar® (codeine, guaifenesin)
• CVS Chest Congestion Relief® (dextromethorphan, guaifenesin)
• Mucinex Fast-Max® (dextromethorphan, guaifenesin)
• PediaCare Childrens Cough and Congestion® (dextromethorphan, guaifenesin)
• Primatene® (ephedrine, guaifenesin)
• Q-Tussin DM® (dextromethorphan, guaifenesin)
• RelCof-C® (codeine, guaifenesin)
• Robitussin Cough and Chest Congestion DM® (dextromethorphan, guaifenesin)
• Safetussin® (dextromethorphan, guaifenesin)
• Tussin DM® (dextromethorphan, guaifenesin)
• Vicks® DayQuil® (dextromethorphan, guaifenesin)
• Zicam® (acetaminophen and dextromethorphan, guaifenesin)