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Date of last update: 10/14/2017.

Forum Name: Gynecology

Question: Abnormal Bleeding and Phentermine

 nes1641 - Fri May 01, 2009 1:49 am

I just started taking the yaz birth control pill about 2 and 1/2 months ago and everything was going perfectly then about a week ago I started bleeding very lightly black brown reddish blood and I also started on phentermine 18.5 mg a day . Could the phentermine be the reason I am bleeding about 2 weeks early and bleeding blackish blood. And if not then why am I bleeding two weeks early and why is it " weird " blood. Thanks
 Debbie Miller, RN - Fri May 01, 2009 12:58 pm

User avatar Hello,
This is called breakthrough or mid-cycle bleeding. It is very common and not a cause for concern. I have never heard of phentermine causing such a side effect and suspect this is just coincidental. The dark color just means it is old blood that for some reason was not eliminated with the last period. Nothing to worry about unless you get continual bleeding -then you should have it checked out.

Best wishes.
 nes1641 - Mon May 04, 2009 3:06 am

How long does this break through bleeding last because I have been bleeding for 2 weeks and does this breakthrough bleeding happen every month...???

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