I am not a UT person, but am able to share with you the amount of time it take for standard medication to get into and out of the body. It's three days. It takes three dosages, or three days to get in and out. There are exceptions, however.
This is what they teach in nursing school anyway.
Good luck
ps. This is a slow forum, but not dead. keep checking back and even after a few days, some one may reply.