http://www.medications.com/effect/view/29483 I am taking Doxycycline for recurrent prostatitis. I have to take 100 mg twice a day for 14 days. It's definitely the worst antibiotic I've ever been on, though it does seem to be generally effective. I'm on day 10 now and I have been on two previous 14 day Wed, 16 Apr 2008 08:48:47 -0400 http://www.medications.com/effect/view/29483?item=7292 Hmm.. I've have chronic prostatitis since 1986. Went though this antibiotic and others off and on for years with little effect. In changing Doctors and diagnosis (many times over many years), I finally went on an alpha blocker, Uroxatral Unlike Flom http://www.medications.com/effect/view/29483?item=7292