A long-acting anabolic steroid, methenolone behaves like testosterone, said Dr. Stanley Korenman, an endocrinologist and distinguished professor of medicine at UCLA's David Geffen School of Medicine.
Methanalone is actually testosterone plus two molecules that have been added to make it last longer than testosterone, which you can't give straight because it breaks down too fast.
When injected, the half life of the drug lasts 11 days, he said. "The substance is all gone in about 30 days."
In other words, if an athlete gets an injection, the substance wouldn't be detectable in month.
Oral forms break down much faster. After a few days, it's gone, said Dr. Korenman.
"In high doses, methenolone increases energy and exercise tolerance, so you can practice for longer periods without tiring," he said. It also builds muscle.
Too much can cause high blood pressure, blood clots, strokes, infertility -- which can be life-long -- and aggression.