E is exstacy, isn't it? I thought that was a combination drug that included a form of speed? If so... he hasn't even switched drugs.
What I have seen is when an addict switches to a drug that is not his drug of choice, he takes is only for a while, then his inhibitions are down and he goes back to his DOC after some time.
For me, an alcoholic, I tried different drinks that I knew I didn't like... but as soon as I got a good enough buzz going, I always switched back to rum and coke.... and 15 a night.
What I have had to learn is to believe actions and behaviors and tune out ENTIRELY the words. More truth happens that way.