first trimester and yeast infection..HELP

Fern

I went to my first OB appointment about a week ago and I was told I have a yeast infection. my OB told me I could take the 7 day monistst OTC. has anyone else used it in their first trimester? I want to take it because the External cream isn't working and the yeast infection is annoying me. I've heard horror stories about using it while in the first trimester. can someone help ease my brain on this.