Codeine (codeine phosphate) contains the active ingredient codeine and is used to reduce pain from headache, the flu and common cold. See here for more information and to order.
A: Mucinex contains the active ingredient guaifenesin, which is an expectorant that helps loosen phlegm and thin bronchial secretions. Mucinex does not have rapid heart rate as a possible side effect. There is a product called Mucinex-D that contains pseudoephedrine, and this ingredient can increase heart rate.
What is Pseudoephedrine? Pseudoephedrine is a medication used to treat nasal congestion, sinus congestion, and a runny nose. These symptoms may be caused by multiple conditions such as the common cold, sinusitis or allergies. Pseudoephedrine only treats symptoms; it is not a cure for viral or bacterial illness.