Steroids: Testosterone Propionate
Propionate is a simple ester with a straight chain of 3 carbons. This causes it to be a rather fast acting ester, which needs to be dosed every 2 to 3 days to keep plasma levels steady. Propionate is a painful injection with swelling and soreness lasting for several days. This is due to the acidic nature of the ester as well as the relative insolubility of the testosterone propionate molecule. This necessitates relatively high concentrations of solvents (such as benzyl alcohol and benzyl benzoate) to be added to the oil to keep the steroid solubilized. Even so, when injected, the steroid can crystallize in the muscle resulting in pain and damage to the tissue. This problem is present even with legitimate pharmaceutical versions of this steroid, however, the underground versions are even worse because they are often formulated with too high of a concentration of steroid and use very high levels of solvent. Even so, some people will inject propionate every day rotating injection sites around the body to avoid having to inject into a location that is still sore from the previous injection. Users tend to see lower incidence of side effects with propionate compared to longer esters partly because a lower total dosage is used. As users increase the dose and the frequency of injection, the propensity for side effects increases.