Testosterone can be administered parenterally , but it has more irregular prolonged absorption time and greater activity in muscle in enanthate , undecanoate , or cypionate ester form. These derivatives are hydrolyzed to release free testosterone at the site of injection; absorption rate (and thus injection schedule) varies among different esters, but medical injections are normally done anywhere between semi-weekly to once every 12 weeks. A more frequent schedule may be desirable in order to maintain a more constant level of hormone in the system.  Injectable steroids are typically administered into the muscle, not into the vein, to avoid sudden changes in the amount of the drug in the bloodstream. In addition, because estered testosterone is dissolved in oil, intravenous injection has the potential to cause a dangerous embolism (clot) in the bloodstream.
In effort to list a protocol for the use of GHRP / GRF / and in combo with GH if desired I thought I would post my current protocol based upon the research I have done within the last year or so. Obviously the information I gathered is not based on medical studies completed by me but I do use the following protocol myself and have been pretty damed impressed with the results. Recovery from injury is very impressive to me (any kind of injury). Example, 5 days ago I was lifted by the butt of a tree I cut down (long story). I had bruising and some serious raspberry on my under arm, left quad and my abs ( the but of the tree ran right up the front of my once it got under my arm it lifted me and tossed me about 10 feet through the air). Its been 5 days and all that is left of the raspberries are some faint red marks......amazing IMO.
Although these molecules are tissue-selective with regards to their effects, they are not perfectly tissue-selective. Some display a disparity of anabolic (*tissue building) versus androgenic (*secondary sexual characteristic promoting) effect as high as 10:1 (although it should be noted that some have a much lower ratio). In practical terms, it would be highly unlikely that an effective muscle building dose would cause any noticeable side effects, and especially not when compared to traditionally prescribed anabolic steroids such as testosterone.