a common solvent used as a preservative in anabolic steroid and other IM injection preparations, is benzyl alcohol (BA). At high concentrations, BA will cause injection pain in the vast majority of users. However in concentrations <10% BA, most will experience little discomfort due to BA. Many people claim that underground laboratories that make injectable anabolic steroids in a non-regulated manner use high BA percentages in their products such as testosterone propionate which is why users experience pain. However, as explained here and in point 2(iii), the BA is unlikely to be the cause of pain. This is why it should be noted that in actual fact, many pharmaceutical preparations contain higher than expected amounts of BA in them. Deca-Pronabol, a pharmaceutically produced form of nandrolone decanoate, contains 9% BA and users generally report no pain associated with its injection. Some preparations of Sustanon-250 by established pharmaceutical companies are made with 10% BA (0.1ml BA per 1.0ml ampoule). However, many would here argue that Sustanon-250 is a sore injection for many. Despite this, when one looks at the make-up of the active ingredients of Sustanon-250, we see a combined testosterone propionate and phenylpropionate amount of roughly 100mg/ml. For reasons discussed in part 2(iii), we may safely assume that the pain is more likely to occur due to the high concentration of these short esters, as opposed to merely high BA concentration. However, it is worth remembering that everyone reacts differently to various solvents and 10% BA may not cause pain for many users, but it will cause soreness for a significant percentage of other users. Other solvents within the preparation apart from the ones outlined here can also contribute or cause injection pain; however the ones discussed are the most significant in the context of anabolic steroid preparations.
