You're a college athlete. You diet. You exercise and practice a lot. But you needed something more, something to give you an edge on all your competition. Steroids and HGH were too easy to detect. Experimental treatments using animal DNA and hormones were much harder to screen for. However, they were expensive and dangerous - unregulated and often manufactured under dubious circumstances.
Fortunately, your close friend was a very intelligent scientist who developed a special drug for you to take to enhance your performance. It seemed to help. There were a few minor side effects, but nothing serious.
But then the fateful mistake: you took much more than the prescribed dose. Maybe it was an accident, or maybe with the biggest competition of the year coming very soon you though a double dose would simply be twice as effective. However it happened, the side effects this time will be very noticeable.