Hi Monica,

My son is on the depot Lupron, but he is taking it as a maintenance drug.  If you are using the Lupron as a substitute for factrel to simulate an LHRH stim. test, then it probably DOES make more sense to use the non-depot Lupron, from what I can tell.  I’ll try to put it into context for you:

The basic difference between the depot and non-depot is that the depot is a long-lasting shot that lasts ~28 days.  The non-depot is short-acting, and normally given daily.

When puberty in a boy happens, the pituitary gland starts to release large amounts of LH and FSH.  These then stimulate the testicles to produce testosterone.  However, this will only happen if LH and FSH are released in a pulsing pattern.  If there is TOO much LH and FSH, so that it is released in a continuous stream, the signals to the testicles will actually decrease, and testosterone production will cease. The way that the Lupron works is that it actually INCREASES LH/FSH production, to produce this continuous stream action. 

If you are doing a stimulation test, I think it does make much more sense to use a short-acting drug, since you are trying to gauge the body’s immediate response to a particular medication.  I suppose it MIGHT be possible to use the long-acting Lupron for the same purpose, but you would need to be very careful about when you drew the blood for analysis of LH and FSH levels, relative to when the injection was given.  In the middle or at the tail-end of the 28 day cycle, the information would probably tell you very different things.

Actually, in general, I think I would be extremely wary of using  a long-acting med in a protocol that is designed for a short-acting med.  The protocol for the non-depot Lupron, I’m sure, is written in such a way as to specify exactly when to draw blood, relative to when the injection is given, and how to evaluate the hormone levels that occur, as a result.  If you substitute a drug that is on a completely different time-line, then I think you’d have to write up a whole different protocol---otherwise, you’d end up with inaccurate information. 

So, while I suppose it is theoretically POSSIBLE to use the long-acting Lupron, I would make sure that the protocol used is appropriate for the particular drug.  But, I guess a more basic question might be WHY your endo wants to use the long-acting Lupron, anyway.  A stimulation test is a short-term event----why use a drug that is designed to last a month, when a different, more suitable drug for the purpose is available?

When my son underwent the LHRH stim. test, a couple of years ago, it was done with the factrel.  After having a positive response, he was then put on the depot Lupron, as a maintenance drug.  From what I understand you saying, you are just trying to figure out if your son even needs the Lupron, right now.  To simulate the factrel, the non-depot Lupron seems much more appropriate.  Once it is determined that he should continue on Lupron, then the depot would be the one that he would stay on.

One last thought:  I am not certain that it is always necessary to do the LHRH stimulation test to confirm puberty.....so that might be something else to speak to your endo about.  When puberty starts, the testicles increase in size and start producing massive quantities of testosterone.  A doctor could probably make some pretty good guesses about the onset of puberty in a boy by assessing the size of the testicles and also by looking at the total amount of testosterone that is being produced.  If puberty has started, testosterone will come from both the adrenal glands and the testicles.  If it hasn’t, then it will be only from the adrenal glands. The hormone "androstenedione" comes only from the adrenal glands.  By comparing the RATIO of testosterone to androstenedione, then, one might also be able to make some guesses as to whether or not testosterone is being produced from one or both places. 

I hope this helps to put things into context for you.