Trenbolone is a steroid used by veterinarians on livestock to increase muscle growth and appetite. To increase its effective half-life, trenbolone is not used in an unrefined form, but is rather administered as ester derivatives such as trenbolone acetate, trenbolone enanthate or trenbolone cyclohexylmethylcarbonate. Plasma lipases then cleave the ester group in the bloodstream leaving free trenbolone.