Arnold did it...haha
But smoking weed and doing roids could have a few potential problems. It wouldn't have the effects that alcohol would have becuase it it being processed through the lungs, not the liver. But I have heard reports of weed upping estrogen levels in the body, which could run you into some problems as well as cardiac changes that occur when you're high.
But really these seem unconsequential to a large extent and I really see no real problems that would exist with smoking and juicing.