What other drugs will affect Nyquil Cold Medicine (acetaminophen, dextromethorphan, doxylamine, and pseudoephedrine)?
Before using this medicine, tell your doctor if you regularly use other medicines that make you sleepy (such as cold or allergy medicine, sedatives, narcotic pain medicine, sleeping pills, muscle relaxers, and medicine for seizures, depression, or anxiety). They can add to sleepiness caused by doxylamine or dextromethorphan. Also your doctor if you are using any of the following drugs: • celecoxib (Celebrex); • cinacalcet (Sensipar); • darifenacin (Enablex); • imatinib (Gleevec); • isoniazid; • quinidine (Quinaglute, Quinidex); • ranolazine (Ranexa) • ritonavir (Norvir); • sibutramine (Meridia); • terbinafine (Lamisil); • zidovudine (Retrovir, AZT); • medicines to treat high blood pressure; • gout medication such as probenecid (Benemid); • an antidepressant; • a beta-blocker such as atenolol (Tenormin), bisoprolol (Zebeta, Ziac), metoprolol (Lopressor, Toprol), propranolol (Inderal, InnoPran), and others; or • seizure medication such as phenytoin (Dilantin) or phenobarbital (Solfoton).