mc7

Yeah, infections like this are pretty common. Unprotected anal sex is essentially an invitation for an infection like this. It takes a lot of careful cleansing to make anal sex not just totally gross, but even then it can still cause infections like this (though it is probably a bit less likely to do so then).

You're asking whether you should take the antibiotic. The only potential negative I can think of with taking the antibiotic is that I would want to be certain the (main) infection is not yeast before taking antibiotics (alone), because antibiotics make yeast problems worse. Because you're not sure what the infection is, I would probably want to take an antifungal along with any antibiotic. That way the yeast doesn't get too much worse from the antibiotic. And yeast is a likely problem unless you know it was tested for (and how helps to know too). There are also kinds of yeast that resist normal culturing methods. There are also some surprisingly common bacteria that resist normal culturing too (like Mycoplasma).

Here are some simple minor urogenital infection fighting tips/home remedies I've tried and liked (and these are all synergistic with any antibiotic):
- Strictly avoid milk and cream (and anything that stimulates mucus production) because these things make it harder to overcome infections (of every sort). All sweets are bad for this too.
- Probiotics can keep yeast out of digestion (if that's an issue). Yeast in digestion encourages yeast infections elsewhere in the body. There are also often other digestive improvements that can have unexpectedly good effects as well. (But it all basically comes down to: just eat well.)
- Cranberry has surprisingly good anti-yeast properties especially for the urinary tract, and it is of some benefit for many other microbial infections too--especially the lower urinary tract (like your urethritis). Unsweetened is much more effective than the common cocktails.
- Cinnamon (of all things) stimulates the immune system from the particular metals & minerals it contains--in normal, small amounts, large amounts can be toxic. It also has mild anti-inflammatory properties.