HCG (human chorionic gonadotropin) is provided as a glycoprotein powder to be diluted with water and taken by injection, either intramuscularly or subcutaneously. It acts in the body like luteinizing hormone (LH), stimulating the testes to produce testosterone even when natural LH is not present or is deficient. It therefore is useful for maintaining testosterone production and/or testicle size during a steroid cycle.
Additionally, outside of or in-between steroid cycles, it can be very useful for increasing testosterone production. The success of this depends on the ability of the testes to actually produce greater amounts of testosterone with increased stimulation. Where the testes themselves are the limiting factor, HCG cannot overcome this.
Including HCG as part of a hormone replacement therapy (HRT) program is superior to relying on testosterone alone if maintenance of sperm production and/or normal testicle size is considered important. Use of testosterone alone can result in infertility or reduced fertility, as normal testicular function depends on higher intratesticular testosterone levels than results from such use.
With regard to steroid usage, HCG should either not be used as part of post-cycle therapy (PCT) at all, or should be used only in a rather precise manner to avoid impeding recovery, shortly to be described.
Post-cycle recovery of LH production requires androgen levels to have fallen back into the physiological range. With use of medium or long-acting esters, this is a slow process. For example, let’s suppose that a given testosterone ester’s half-life is 7 days, and that 800 mg/week was used during the cycle. If so, then one week after the last injection, levels will be similar to what they would be if 400 mg had been taken weekly for some time, and with another 400 mg having just been injected. At the two week point after the last injection, levels will be commensurate with ongoing 200 mg/week use.
This is without using HCG during this period.
But if HCG were used during this time, or started at this point, testosterone levels would be similar not to those of ongoing 200 mg/week usage, but to that level plus another 100-200 mg/week of equivalent increase from HCG. This would interfere with recovery of LH production.
The better plan is, if using HCG, to employ it during a cycle to maintain testicular function so that the testes will be responsive to LH as soon as its production is restored. There will also be the advantages of maintaining testicle size and of providing some additional testosterone via HCG-stimulated production.
This last point will be of no great importance when a large amount of steroids is being used weekly, but can be quite significant if the total milligram amount is modest.
Such added testosterone production is of particular value if a stack is entirely non-aromatizing and dosed high enough to be fully inhibitory of natural testosterone production. In that situation, estrogen levels would fall abnormally low unless or HCG is taken to yield normal testosterone levels during the cycle, as estradiol is produced from testosterone.
The traditional HCG dose was 5000 IU at a time. While this produces blood levels representing a vast overdose for at least the first week after injection, this dosage had a medical use as in many cases it is desirable to administer only a single injection, or infrequent injections, than to require two or more office visits per week for injection. And as the half life is only a few days, an extremely high initial level is required to obtain extended duration of action from a single injection.
This dosage is far more than should ever be used in bodybuilding or for hormone replacement therapy.
My previous recommendation of 500 IU/day as being generally sufficient was a radical break from bodybuilding practice at the time, which employed far higher doses that gave HCG a reputation as a harsh drug; but further experience as well as a medical study on the matter published in 2005 by Coviello et al. has shown that even less than that is needed.
Little if any difference exists in resulting testosterone production between dosings of 250 IU every other day (EOD) and 500 IU EOD. Dr Eugene Shippen has also found low-dose use effective in extensive clinical practice, and bodybuilding practice has also shown such doses to be completely effective.
Accordingly I now consider a dosage of 500 IU EOD (or 3x/week, which is nearly equivalent), or 250 IU daily to represent a reasonable absolute maximum.
As values for general use, 100 IU daily, 200 IU EOD, or 250 IU three times per week are very effective. The medical study mentioned above found no significant difference in results between this dosage level and the above recommended absolute maximum, but it may be the case that for some individuals there could be some small difference.
At these doses, unlike what is the case with vast overdoses, HCG has no perceptible side effects.
As a part of PCT, as already explained HCG should not be used during that period in which inhibition would result from the combination of the resulting testosterone production and the remaining levels of injected steroid. However, upon levels of injected steroid falling below what would be commensurate with 100 mg/week use, very low dose HCG such as 100-125 IU every other day is acceptable as a part of PCT.
Preparing hCG: Convenient dilution ratios are values such as 1000 or 2500 IU per mL. Once mixed, the preparation should be refrigerated and used within a few weeks. If the reconstituted amount is greater than can be used in such a period of time, it is acceptable to freeze portions of the preparation for later use. The substance is also somewhat temperature sensitive before mixing and should not be exposed to excessive heat. Refrigeration is required for long-term storage, but unreconstituted HCG can withstand at least two months at ordinary room temperature.