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Dr. Andrew Rynne
Dr. Andrew Rynne

Family Physician

Exp 50 years

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Does birth control pill interact with Hyoscyamine?

Answered by
Dr. Sameer Kumar

OB and GYN Specialist

Practicing since :2002

Answered : 1656 Questions

Posted on Mon, 19 Sep 2016 in Pregnancy
Question: Hi Doctor. My girlfriend takes both birthcontrol pills and hyoscyamine. I see that this interation decreases BC's effectivness. Am I still safe to have sex?

Hi doctor, my girlfriend takes both birth control pills and hyoscyamine . I see online that this can decrease the effectiviness of both birthcontrol pills and plan b. I didnt figure this out until we had a night of sexual intercourse. I had her take plan b the next morning. Am I okay? How much does hyoscyamine decrease their effectivness? Will she become pregnant
Answered by Dr. Sameer Kumar 44 minutes later
Brief Answer:
yes , it decreases effectivity.

Detailed Answer:
Thanks for the query to HCM,

Hormonal birth control (eg, birth control pills) may not work as well while you are using hyoscyamine. To prevent pregnancy, use an extra form of birth control (e.g., condoms). The effectiveness is decreased by 30-40 percent on regular intake of hyoscyamine and daily BC pills. So its best to use an additional contraceptive for at least a week after the hyoscyamine use has been discontinued.
So there may be a chance of pregnancy if she has ovulated. She has taken plan b , thats fine, now wait for her withdrawal bleeding within 7-10 days, to initiate which shall ensure that she is not pregnant.
Above answer was peer-reviewed by : Dr. Chakravarthy Mazumdar

The User accepted the expert's answer

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