The recommended dosage of Mucinex tablets containing 600 milligrams of guaifenesin is up to two tablets every 12 hours with a maximum of four tablets every 24 hours, reports the manufacturer, Reckitt Benckiser. Children 11 years old and younger should not use this medication.
Patients should consume Mucinex tablets whole with plenty of water, according to the U.S. National Library of Medicine. The product can be taken at mealtimes but does not need to be. Mucinex's active ingredient, guaifenesin, acts as an expectorant to thin bronchial secretions, loosen mucus, increase the productivity of coughs and move phlegm from the lungs.