Human Growth Hormone is an injectable hormone that can be administered subcutaneously or intramuscularly. When injected subcutaneously, HGH carries a bioavailability of approximately seventy-five percent. When injected intramuscularly, HGH carries a bioavailability of approximately sixty-three percent. The mode of administration will also affect the half-life of the Somatropin hormone. When injected subcutaneously, it will carry a half-life of approximately hours. When injected intramuscularly, it will carry a half-life of approximately hours. While this is a rather short half-life regardless of the mode of administration, keep in mind the total effects far outlast these numbers due to the pronounced and significant increases in IGF-1 production that stretch far past the twenty-four hour mark.
Injectable steroids are injected into muscle tissue, not into the veins. They are slowly released from the muscles into the rest of the body, and may be detectable for months after last use. Injectable steroids can be oil-based or water-based. Injectable anabolic steroids which are oil-based have longer half-life than water-based steroids. Both steroid types have much longer half-lives than oral anabolic steroids. And this is proving to be a drawback for injectables as they have high probability of being detected in drug screening since their clearance times tend to be longer than orals. Athletes resolve this problem by using injectable testosterone early in the cycle then switch to orals when approaching the end of the cycle and drug testing is imminent.