Cold or allergy medicine, sedatives, narcotic pain medicine, sleeping pills, muscle relaxers, and medicine for seizures, depression or anxiety can interact with Phenergan and cause medical problems or increase side effects. Tell your doctor if you regularly use any of these medicines.
Also tell your doctor if you are using any of the following medicines:
lithium (Eskalith, Lithobid);
atropine (Atreza, Sal-Tropine), belladonna (Donnatal, and others), benztropine (Cogentin), dimenhydrinate (Dramamine), methscopolamine (Pamine), or scopolamine (Transderm-Scop);
blood pressure medication such as guanadrel (Hylorel), guanethidine (Ismelin), propranolol (Inderal), and others;
a blood thinner such as warfarin (Coumadin);
bronchodilators such as ipratropium (Atrovent) or tiotropium (Spiriva);
bladder or urinary medications such as oxybutynin (Ditropan, Oxytrol), solifenacin (Vesicare), and others;
a MAO inhibitor such as isocarboxazid (Marplan), tranylcypromine (Parnate), phenelzine (Nardil), or selegiline (Eldepryl, Emsam) or methylene blue injection; or
medicines to treat Parkinson's disease, restless leg syndrome, or pituitary gland tumor (prolactinoma); or
medicine to treat stomach ulcer or irritable bowel syndrome, such as dicyclomine (Bentyl), glycopyrrolate (Robinul), hyoscyamine (Anaspaz, Cystospaz, Levsin, and others), mepenzolate (Cantil), or propantheline (Pro-Banthine).
This list is not complete and there are many other medicines that can interact with Phenergan. Tell your doctor about all your prescription and over-the-counter medications, vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start a new medication without telling your doctor. Keep a list with you of all the medicines you use and show this list to any doctor or other healthcare provider who treats you.
 Phenergan drug interactions (more detail)
