Q: What’s the logic behind all the different timing and dosing of HCG ?? We hear taking it every day, every other day, every 3rd, 4th, or 5th day.
What about the dosing ? I hear to take it easy to prevent desensitizing the testes. With this you hear anywhere from 100 units to 250 units to play it safe. Others say anywhere from 500 to 2500 units at a time…Isn’t that a bit much ?
What about the length of time? I hear two clinics suggest 10 days; others say 3-5 weeks. Where does all this come from and who’s right?
A: Almost everything you hear or read will be anecdotal and therefore subject to no verification. Experiences with hCG while on TRT are posted. The use of hCG for PCT is only partly related to its use on TRT.
hCG while on TRT is used for two reasons. One reason is cosmetic. While on TRT it is not unusual and more often expected to have testicular atrophy. This is variable from individual to individual. The other reason is to act as a stimulus so the testicles do not shut down and therefore will be easier to initiate independent function after AAS cessation.
Desensitization is a potential problem with hCG. I do not think you will experience it with doses of 500IU or less 3X/week. Studies have used this dose for considerably long periods. In my patients when hCG was used while on AAS the dose was 1000IU every 3 days with one month on hCG followed by one month off hCG.
hCG for PCT involves additional concepts. This is the timing of hCG in relation to other medications for return of HPTA functionality. Under normal conditions the HPTA is a tightly coupled dynamic feedback loop. It is this coupling that has to be achieved after AAS cessation to return to normal. The analogy I use is the starting of a car by pushing it from behind. Alone the care will not start but with pushing the clutch can be popped and the car started.
After AAS cessation the secretion of LH is nil. It will not be able to initiate T production until a certain stimulus LH level is reached. Studies have shown that the time for this to occur can be lengthy. Thus the idea is to ‘push’ the testicles with hCG and get them started. Once T production is initiated the dependent variable is LH. If the hCG is withdrawn without adequate LH to couple with the testicles return of HPTA functionality will fail.
The increased production of LH is achieved by a dual action of clomiphene citrate and tamoxifen. Clomiphene is a mixed agonist/antagonist (SERM) at the estradiol receptor. Clomiphene will increase the secretion of LH by action at the hypothalamo-pituitary area. Clomiphene will cause an increase in LH and secondarily increases in T and estradiol. Estradiol has a negative feedback influence on the HPTA. Estradiol is 200X the inhibitory effect of T per molar basis. Normal serum levels are the following:
Testosterone: 3-10 ng/ml (10-35 nM/L)
Estradiol: 15-65 pg/ml (55-240 pmol/L)
Tamoxifen will counteract the effect of the estradiol. Once the hCG is withdrawn the LH, initiated by clomiphene and tamoxifen, will couple with the testicles and take over production of T by the testicles. The levels of LH to maintain and couple with the testicles are maintained by clomiphene and tamoxifen. Clomiphene is continued for 15 days while Tamoxifen is continued for 30 days.
In healthy adult men, circulating levels of testosterone have a distinct pattern, with increasing levels during sleep toward a maximum around the time of awakening and a decrease during the day. In PCT hCG is administered every other day. I suggest the same time each injection in an attempt to simulate this rhythm. This is purely empirical but I recommend hCG at bedtime (2200). Clomiphene is taken in divided doses of 50mg 2X/day.