How long Lupron stays in your system depends on the dosage you were given, i.e. one month, 3 month or 6 month injection. When a Lupron injection is given it is slowly released into the blood stream. It has its effect directly on the pituitary gland and mimics a naturally occurring hormone to signal to the pituitary to stop production/release of 2 hormones-FSH and LH. LH is primarily responsible for telling the testicles to produce testosterone. As a result, the testosterone levels rapidly fall, temporarily stopping cancer growth and killing some cancer cells. Other than that, Lupron really has no other effects on the body and once in the bloodstream is rapidly broken down.

When men stop Lupron there is a variable length of time before (if) the LH released from the pituitary gland increases to tell the testicles to restart production of testosterone. When and if testosterone returns is dependent on 1) age 2) length of time on ADT/Lupron 3) pretreatment level of the man's testosterone.

Whether the PSA rises as the testosterone returns is variable. Some men see their PSA go up (indicating cancer growth) as the testosterone goes up and others don't.

I agree that ADT/Lupron can be a devastating drug although it is life saving. I had virtually all the bad side effects of Lupron. When the Lupron was discontinued by my MO (after 1 year) my PSA was undetectable and has remained so. After 18 months off Lupron my testosterone never recovered. My MP put me on TRT. The return of my testosterone has been life changing for me. Return of feeling of well being, energy, libido etc.

Good luck to you.