How long does penicillin stay in your system?

Answer 1

About 95 percent of the penicillin should be out a system within 10 hours. It may be detectable for up to about 2 days.

Answer 2

The amount of time that penicillin stays in the system of a cow depends on the amount given. The more given the longer it stays.

Answer 3

Only a very small amount of penicillin is excreted into breast milk. Duration data is not available.