How long does doxylyn take to clear up the std? and after how long can i stop using it?

Which STD?: Doxycycline (Doxylin and many other brands) treats some STDs but not all; it depends on which infection you have. Usually 7 days for chlamydia, nongonococcal urethritis (NGU) in men, and partners of people with these STDs. 2-4 weels for syphilis. 10-14 days for pelvic inflammatory disease (PID) when the exact cause is not known. Not reliable in any dose for gonorrhea. No effect on HPV or herpes.