Steroids can make pimples pop up and hair fall out. They can make guys grow breasts and girls grow beards. Steroids can cause livers to grow tumors and hearts to clog up. They can even send users on violent, angry rampages. In other words, steroids throw a body way out of whack. Steroids do make users bulk up, but the health risks are high. It's true, on steroids biceps bulge; abs ripple; and quads balloon. But that's just on the outside. Steroid users may be very pleased when they flex in the mirror, but they may create problems on the inside. These problems may hurt them the rest of their lives. As a matter of fact steroid use can shorten their lives.
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 . 
2. A different study examined the effect 300mg of Modafinil had on participants. In this study a placebo or 300mg dose of Modafinil was administered to participants. All participants were non-sleep deprived, healthy adults. The participants attended three different 50 minute cognitive testing sessions. One session occurred before the Modafinil or placebo was administered, one occurred 90 minutes after ingestion, and the last one occurred 180 minutes after ingestion. Testing included not only subjective assessments of fatigue, mood, and motivation but cognitive assessments were also conducted.