There are two types of Dianabol that shoppers will encounter no matter where they look: pharmaceutical grade Dianabol and underground lab (UGL) grade Dianabol. As the names imply, pharmaceutical grade drugs are those which are manufactured by fully licensed and FDA-approved pharmaceutical companies that manufacture these drugs for sale on the prescription market. However, in the case of off-label use for bodybuilding and athletic purposes, these drugs are often diverted clandestinely into the black market. UGL products are simply manufactured by unlicensed, unapproved, and often amateur underground laboratories that sell their products for far cheaper than their pharmaceutical grade counterparts.
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The most commonly used AAS in medicine are testosterone and its various esters (but most commonly testosterone undecanoate , testosterone enanthate , testosterone cypionate , and testosterone propionate ),  nandrolone esters (most commonly nandrolone decanoate and nandrolone phenylpropionate ), stanozolol , and metandienone (methandrostenolone).  Others also available and used commonly but to a lesser extent include methyltestosterone , oxandrolone , mesterolone , and oxymetholone , as well as drostanolone propionate , metenolone (methylandrostenolone), and fluoxymesterone .  Dihydrotestosterone (DHT; androstanolone, stanolone) and its esters are also notable, although they are not widely used in medicine.  Boldenone undecylenate and trenbolone acetate are used in veterinary medicine .