Why can't I find a unanimous answer?

iVillage Member
Registered: 03-27-2004
Why can't I find a unanimous answer?
6
Sat, 04-17-2004 - 10:44pm
I've been looking all over the net for information on antibiotics and birth control effectiveness. I've found medical sites that say the research that concludes that birthcontrol is less effective when on antibiotics to be fairly inaccurate and that the pregnancy results may have been from other factors. Then I find sites that say that certain antibiotics (ie., PCN, Ampicillin) do effect birth control. It's just so frustrating. Some say sulfonamides (the SMZ in the SMZ-TMP, I believe), some do not.

I take Seasonale BCP, and I've been on Bactrim (SMZ-TMP) for the past 5 days for a UTI and was pretty good this weekend (using condoms) with my boyfriend, until we were fooling around and he penetrated me a few times - but he did not "finish". Now I know the chances are very slim that anything will come of it, but it's just frustrating to not find a unanimous decision on such a topic as this.
iVillage Member
Registered: 12-30-2003
Sat, 04-17-2004 - 11:03pm
Hi Wlm1213, welcome!

I know, it is frustrating. You can ask you doctor or the pharmacist who dispensed your Bactrim and see what s/he says. It’s my understanding that some antibiotics can reduce the effectiveness of hormonal contraceptives in some women and it’s not known who they will be beforehand. Therefore, this board recommends using back-up while taking all antibiotics and anti-seizure meds. and continuing to use back-up for at least 7 days after finishing the last dose. Better to be safe than sorry, right?

Good luck

      Jill

    

iVillage Member
Registered: 03-27-2004
Sat, 04-17-2004 - 11:26pm
Thanks for the response! I looked up Bactrim on a medical site already and it does not mention anything about birthcontrol, only sunlight sensitivity. Sulfonamides are part of the drug, and that's what I heard may decrease effectiveness. My dr didn't say anything and she knows I'm sexually active. BF and I agreed that we were a bit careless, and will just be playing it safe permanently.

iVillage Member
Registered: 03-27-2004
Mon, 04-19-2004 - 6:47pm
Just an update: Though I'm sure my BF and I have nothing to worry about - I looked up emergency contraception on the internet and was able to find the e.c. equivalent for my particular birth control. I took 2 pills this morning before I looked it up ---and it turned out to be 4 pills within 120 (5 days) of intercourse and then 4 more pills 12 hours later. Probably nothing to worry about, but hey, it won't hurt!
iVillage Member
Registered: 01-15-2003
Mon, 04-19-2004 - 6:58pm
You're right, it won't hurt - as such... but do be aware that large doses of hormones (such as e.c. or extra birth control pills) can cause irregular bleeding. Don't be surprised if your next period isn't when expected and/or the same sort of bleeding pattern as usual. You could also spot in the several days following the ingestion of extra pills.

Good Luck, I'm sure you'll be fine.

iVillage Member
Registered: 03-27-2004
Mon, 04-19-2004 - 7:10pm
As long as it comes! That's what counts! :-P
iVillage Member
Registered: 03-27-2004
Mon, 04-19-2004 - 10:11pm
Just FYI, I used to take BCP until my blood pressure started havng problems. I get recurrent UTI's and my Dr., pharmacist, etc. were all in agreement that Macrodantin wouldn't decrease the effectiveness of BCP. This is what I took for my UTIs (averaged about 1 every 6-8weeks)for 10 years while on BCP with no slipups. If you get another one, you might ask about that antibiotic...there isn't any sulfa in it at all as I'm allergic.