Hello, I'm a 28 year old female i weight 90kg and in good health. I'm on nuvaring and finished a 5day zpack and 5 days of coricosteroides, 3 weeks ago. The nuvaring website says broad-spectrum antibiotics do not interact with it, but the pharmacist says it does. I'm also on 75mg daily PO topamax for migraines, taking this for 6 months now. Sevear nausea has started a week ago. Sudden onset of nausea for me usually means im pregnant. I have not been exposed to the flu or has anyone in my house received the flu vaccine. I took a home pregnancy test that resulted negative. Should I stop my topamate till I know if I'm pregnant or not? Should I ask my doctor for a blood serum level? Thank you.