Oooh man, I feel her pain. Have you gotten Azo? It's recommended by doctors and has cleared up both of the UTI's I've ever gotten in a snap, even one really bad one. I wish I'd known about it sooner!

Make sure you never go from anal sex to vaginal sex or anything like that. UTI's are caused by bacteria being pushed or trapped in the urethra. Peeing after sex does help prevent them from occurring, so try to make that a regular practice for the two of you as much as it sucks. Also, UTI's can be caused by wearing non-cotton underwear (lots of thongs are made out of some kind of lycra/spandex/polyester material), wearing too tight or damp clothes (not letting your clothes dry all the way in the dryer), not changing your underwear/pads/tampons often enough, and even using scented feminine or bath products.

Get some regular Azo meds (no prescription needed, you can get them at walgreens or walmart), stay awwaaay from sweetened cranberry juice or sodas, and take as many precautions as you can. UTIs are hoorrrible, and reoccuring ones and those that go for long periods of time untreated can cause scarring. Good job for being so concerned about your girlfriend. WHen my husband and I first began having sex while we were dating, I got UTI's too. It's okay

Taking Azo does not cure a UTI. A UTI is an infection and you need to see a doctor for that. Azo WILL, however, help with the pain, burning and urgency.

She needs to keep seeing a doctor - and use the bathroom after sex. It helps to wash out all the bacteria.

go pee right after having sex. i got utis really bad but since i've been peeing after sex i have had no more problems.

Yep- make sure she pees. It sounds dumb but once I started religiously peeing right after I stopped getting them.

UTI's in women can be a part of sex, unfortunately. I was told to pee before & after. If you're not circumcised be sure to clean really, really, really good. When I get one I drink tons of water & take cranberry pills.
Ingi is right about seeing a dr. though. Any infection can get serious if it's not taken care of. I'm not sure, but at 18 she should be able to legally go to the dr. on her own. Does anyone know? Besides, you wouldn't want to deal with a doc that prescribed drugs withhout seeing her. Once she's established with a doc, sometimes they will call in a script for antibiotics for a UTI if they've already treated the patient for them once or twice.

I agree with the others who advised she see a doctor. Recurrent UTIs should be treated with antibiotics. Be sure that she finishes the antibiotic treatment-if you stop taking the drugs when you start feeling better, the infection will come back. She seems to be prone to them, so she should pee after having sex and also try to keep drinking enough water daily.