Many drugs can interact with ethinyl estradiol and levonorgestrel, and some drugs can make hormonal birth control less effective, which may result in pregnancy. Tell your doctor about all your other medicines, especially:
acetaminophen, aprepitant, ascorbic acid (vitamin C), bosentan, levothyroxine, St. John's wort;
antibiotic or antifungal medicine - fluconazole, griseofulvin, itraconazole, ketoconazole, rifabutin, rifampin, voriconazole;
antiviral medicine to treat HIV or hepatitis C - atazanavir, boceprevir, darunavir, efavirenz, etravirine, fosamprenavir, indinavir, lopinavir, nelfinavir, nevirapine, ritonavir, telaprevir, tipranavir;
cholesterol medicine - atorvastatin, rosuvastatin; or
seizure medicine - carbamazepine, felbamate, lamotrigine, oxcarbazepine, phenobarbital, phenytoin, rufinamide, topiramate.
This list is not complete and many Other drugs may interact with ethinyl estradiol and levonorgestrel. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.
 Twirla drug interactions (more detail)
