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 . 
[ Editor's Note: Chryste Gaines, MBA, Olympic gold and bronze medal sprinter and former teammate of Marion Jones in the 2000 Sydney Olympic Games, stated the following in a Dec. 22, 2008 email to in response to the IOC ruling:
"We are being unfairly punished. If the drug testing agencies cannot determine if an athlete is taking performance enhancing drugs how are the teammates supposed to know?... It negates all the family functions, church functions, and social events we missed in the name of winning an Olympic medal." ]
Health records shall contain the date the lot was established (if using the unique lot method), the first date the animal(s) may be shipped for slaughter considering the requirement for at least a 180 day recorded history prior to slaughter, the unique identifier, as well as record entries that indicate the date the illness was noticed, the details of the illness, the number of animals affected and date the illness was resolved. Each record event entry shall be accompanied by the initials of the person making the entry and date/time of the entry.