compare use and effectiveness of maxiphen & musinex ## It really depends on the brand of Mucinex you get, because some packages contain Guaifenesin + Phenylephrine; while the standard brand of Maxiphen already contains both of these. I think the standard Mucinex only contains Guaifenesin from what I can tell (there are many different variations of Mucinex/D/DM/DM For Kids/etc). Some also contain a different combination of Guaifenesin + Dextromethorphan (kids version). That said, there are no differences between these two medications, since they both "can" contain the same active ingredient(s) depending on which one you choose. It may just come down to personal preference when trying to decide which one works best for you. If you follow the link below and scroll towards the b...