Tested positive for rectal chlamydia, took 1000 mg azithromycin, no sexual contact at all, but still symptoms. re-tested 3 weeks later, if it's positive again should i ask for a different antibiotic?

Here are some ...: I'm glad and impressed with your higher personal diligence and vigilance in assessing STD than most of men around. As to retreating with different antibiotics, I strongly suggest to refer all currently related Qs to the existing Doc for better pertinence and correlation so to deduce better timely care and outcome ... Best wish ...

Longer treatment: The single dose of Azithromycin may not be sufficient in cases of rectal infection. Doxycycline 100mgm twice daily for WEEK may be your next step. SEE YOUR HEALTH CARE PROVIDER..

Chlamydia: Chlamydia is a sexually transmitted disease that should be treated quickly in order to avoid complications. Azithromycin is an antibiotic usually prescribed in a single dose, while doxycycline must be taken twice per day for about one week. This usually takes two weeks at most, during which time you will need to refrain from sexual contact. Your doctor will make the treatment plan.