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.
Pseudoephedrine is a decongestant medication sold over the counter (such as in Sudafed). It is also found as a component in some prescription medications. Pseudoephedrine is available as a tablet, chewable tablet, controlled-release tablet, capsule, syrup, suspension and liquid and as drops. This drug is indicated for nasal congestion and congestion of the Eustachian tubes.