How long do chlamydia symptoms last after taking a single dose of 1000mg azithromycin?

A few days: The usual symptoms of chlamydia in men are penile discharge and sometimes discomfort passing urine. Both should start to improve in 2-3 days, but up to 10 days to clear entirely. Azithromycin is very long acting, in your system for 7-10 days after a single dose, so slow improvement usually doesn't mean more treatment is needed. Contact the doc or clinic treating you if you remain concerned.