ephedra is anti-catabolic since it increases protein synthesis.
Coke will burn muscle for a few reasons. First, it does increase your metabolism to a very high level, causing you to burn muscle. Secondly, you probably won't be able to eat and your body will then take nutrients from muscle, and get it's energy from there before it even starts to attack fat. lastly, coke dehydrates you. Dehydration is extremely catabolic.
There are reasons why certain drugs are used by bodybuilders, and some never made it (like fenfen). Most things just decrease muscle size and bone density.