What other drugs affect Codeine Guaifenesin?
Before taking this medication, tell your doctor if you regularly use other medicines that make you sleepy (such as allergy medicine, narcotic pain medicine, sleeping pills, muscle relaxers, and medicine for seizures, depression, or anxiety). They can add to sleepiness caused by codeine and guaifenesin. Also tell your doctor if you are using any of the following drugs: cimetidine (Tagamet) quinidine (Quinaglute, Quinidex, Quin-Release) naloxone (Narcan); or naltrexone (Vivitrol) This list is not complete and there may be other drugs that can interact with codeine and guaifenesin. Tell your doctor about all the prescription and over-the-counter medications you use. This includes vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start using a new medication without telling your doctor.