Intramuscular Use of HCG
Intramuscular use of HCG gets the drug into the plasma much quicker than the subcutaneous method. Also, much more of the drug is available at the action site (the leydig cells) at a given time. The advantage to this is a more potent activation of the cells if they have been suppressed to a greater extent.
Intramuscular use of HCG can also be used as a quick jump-starter to allow a faster onset of recovery and stimulation of testosteorne. This is very useful if you are a seasoned user or one of our...ummm...permanent replacement individuals before permanent replacement age. You know, from your 20's to early 30's and never seem to go off. Yeah, if thats you, you probably want to go the intramuscular route because your leydig cells have had a long, deep, nap. More like a hibernation.
"Theoretically", you could always use a large intramuscular dose of HCG to jump start the testis. Then follow up with smaller, more physiologic doses of HCG until you feel healthy and have recovery of your testosterone and testicular size.
Subucutanous Use of HCG