Testosterone cypionate is an analytical reference standard categorized as an anabolic androgenic steroid. Testosterone cypionate is an ester of the naturally occurring androgen, testosterone (ISO60154) with a longer half-life.¹ Formulations containing testosterone cypionate were previously used for patients with hypogonadism; however, additional esters of testosterone have been synthesized that provide improved pharmacokinetics.² Anabolic steroids, including testosterone cypionate, have been used to enhance physical performance in racehorses and athletes.^3,4 This product is intended for research and forensic applications.