guaifenesin
Anti-Tuss, Balminil Expectorant ◆, Breonesin, Diabetic Tussin EX, Duratuss-G Fenesin, Gee-Gee, Genatuss, GG-Cen, Glyate, Glycotuss, Glytuss, Guafenex LA, Humibid LA, Humibid Sprinkle, Hytuss, Hytuss 2X, Mucinex, Muco-Fen-LA, Mytussin, Naldecon Senior EX, Organidin NR, Respa-GF, Resyl ◆, Robitussin, Scot-Tussin, Touro EX, Tusibron, Uni-tussin

Available forms
Available by prescription only
Capsules: 300 mg
Tablets: 1,200 mg
Tablets (extended-release): 600 mg, 1,200 mg
Capsules: 200 mg
Capsules (extended-release): 300 mg
Syrup: 100 mg/5 ml, 200 mg/5 ml
Tablets: 100 mg, 200 mg
Tablets (extended-release): 600 mg

Indications and dosages
 Expectorant. Adults and children age 12 and older: 100 to 400 mg P.O. q 4 hours. Maximum, 2.4 g daily.
Children ages 6 to 11: 100 to 200 mg P.O. q 4 hours. Maximum, 1.2 g daily.
Children ages 2 to 5: 50 to 100 mg P.O. q 4 hours. Maximum, 600 mg daily.
Children younger than age 2: Individualize dosage.
Extended-release form Adults and children older than age 12: 600 to 1,200 mg P.O. q 12 hours. Maximum, 2,400 mg in 24 hours.
Children ages 6 to 12: 600 mg P.O. q 12 hours. Maximum, 1,200 mg in 24 hours.
Children ages 2 to 6: 300 mg P.O. q 12 hours. Maximum, 600 mg in 24 hours.

Pharmacodynamics
Expectorant action: Guaifenesin increases respiratory tract fluid by reducing adhesiveness and surface tension, decreasing viscosity of the secretions and thereby facilitating their removal.

Pharmacokinetics
Absorption: Unknown.

Contraindications and precautions
Contraindicated in patients hypersensitive to drug.

Interactions
None significant.

Adverse reactions
CNS: dizziness, headache.
GI: vomiting, nausea (with large doses).
Skin: rash.

Effects on lab test results
None reported.

Overdose and treatment
No information available.

Special considerations
• Efficacy of guaifenesin as an expectorant hasn’t been clearly established because of conflicting results of clinical studies.
• Reevaluate patient if symptoms persist for longer than 1 week, if cough recurs, or if cough is accompanied by fever, rash, or persistent headache.
Breast-feeding patients
• It isn’t known whether drug appears in breast milk. Safety in breast-feeding women hasn’t been established.
Pediatric patients
• Individualize dosage for children younger than age 2.
Geriatric patients
• No specific recommendations are available. Most liquid forms contain alcohol (3.5% to 10%).

Patient education
• Advise patient to take drug with a glass of water to help loosen mucus in lungs.
• Advise patient to use sugarless throat lozenges to decrease throat irritation and cough and to report cough that persists longer than 7 days.

Reactions may be common, uncommon, life-threatening, or COMMON AND LIFE THREATENING.
◆ Canada only
◇ Unlabeled clinical use