Does azitromycin cure chlaymdia in the rectum? i read that it was ineffective?

Usually yes, but...: You're asking a question whose answer is changing by the month. Azithro was always considered equally effective as doxycycline both for genital and rectal chlamydia, but new research shows it's not as reliable as doxy. Some STD clinics recently started using doxycycline in preference to azithro for rectal chlamydia. But azithro still 90% reliable; if already treated, don't re-treat, just re-test.