I have a history of UTIs and have taken several different antibiotics over the last few years. Currently I'm taking Bactrim and I took it last time I had a UTI as well. Last time it caused me to get a yeast infection, an no other antibiotic does this for me and I woke up with a HUGE swollen lip. I didn't think anything of it and figured I had bit my lip in my sleep, but I just started taking Bactrim again a couple days ago and here it is again: Another yeast infection and my top left side of my lip ballooned up. My doctor ignored my statement about the yeast infection when he prescribed Bactrim last week, but you can bet he's going to listen when I go back tomorrow!! I already took tonight's dosage, but I'm not going to take tomorrow morning's and get in to see the doctor asap. Not only is my lip swollen, but it gets more and more painful as time passes and it slightly itches.