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.
You may have noticed that erectile dysfunction related human studies for this supplement are lacking. Well, all I can say is all those rats couldn't have been that wrong. Steven Lamm, . in his excellent book, The Hardness Factor , uses it in his practice and says that many of his patients swear by it. He performed a (non peer-reviewed) HGW study on 38 men. 25 were healthy men and 13 were taking Viagra. About two thirds of the healthy men and about half of the men using Viagra responded positively to the Horny Goat Weed. Of course, this is not a rigorous study, since the placebo effect was not taken into account, but it's a good sign nonetheless.