Winstrol differs from other injectable anabolic steroids in being an aqueous suspension of fine particles of steroid, instead of being
an oil solution of an esterified compound. For this reason, it has unusual pharmacokinetics which do not follow the classic half-life
pattern. Instead, there is a sustained effect which slowly tapers. The duration of action is probably at least a week. Individual
particles of stanozolol may remain at the injection site for extended periods of time, however, which can cause drug test failure.