How long does it take Cipro to leave your system?

One 500mg dose of Cipro works for 12 hours. One 500mg tablet has a four hour half life - meaning it takes approximately eight hours for one 500mg dose to be eliminated from your bloodstream; that is, after the initial 12 hours that the drug is working in your system. So, if you took one 500mg tablet at noon, by approximately 8AM the next morning, it should be eliminated from the bloodstream, considering you do not take a second dose before that time. Otherwise, you have to account for each dosage you take.