I was told by my pharmacist that taking topriamate (generic for topamax) at the same time as birth control could lessen the effectiveness of the birth control. yet my doctor who prescribed the topriamate said i would be fine as long as i only used 100 mg. my gynocologist also said it was fine. yet the pharmacist said if i had spotting between periods it was a sign that the birth control was less effective. i have only had spotting once for a small amount and i have been on this medicine since early summer. Is it less effective now?