Thread: Cramping after taking antibiotics with my birth control

Hi Panda,

Antibiotics shouldn't have made you cramp even combined with birth control, but they could have weakened it, but like you said you avoided sex, so you shouldn't be pregnant. But perhaps you don't have enough of it in your system, so you are re-experiencing the symptoms that made you want to take it in the first place? That sounds the most plausible solution to me.

The reason why your doctor tells you to abstain from sex or use additional protection if you are on antibiotics and using an oral contraceptive is because antibiotics tend to wipe out your normal flora (the bacteria that normally live within your gut). Estrogen is fat soluble, and once it goes through your liver, your liver is going to metabolize it in order to remove it from your body through a process known as glucuronidation. Basically what this process does is make estrogen water soluble, which is a problem, because now instead of having the estrogen within your tissues, it is going to be in your bloodstream where it will go through the kidneys and be excreted from your body. This is where your normal flora come into play, because they act to deglucuronidate estrogen so that it can be reabsorbed into your tissues, and not excreted from your body. So that cramping that you were feeling was likely due to you not receiving a high enough dose of estrogen. Some antibiotics have been proven to be worse than others for "weakening" birth control, but it is definitely best to use a back-up method of protection when you are taking an antibiotic just to be on the safe side.