If it is something on the NHL banned substance list then IIHF would already be giving him a ban, since their anti-doping rules are more strict (as we could see from Zaripov's example).
Here the situation is a bit more strange: 5 guys are 'not invited': Belov, Plotnikov, Nichushkin, Naumenkov and Bereglazov. Belov isn't because he had a banned substance history (and the IOC made it clear that you need to have your history nice and shiny), so that's not a surprise. Plotnikov didn't have a ban, but apparently at some point was given a warning (probably the substance was not a big deal), so there is some sense too. Naumenkov and Nichushkin didn't have any ban/warning history and that was stated officially; IOC, of course, didn't provide any explanation. For Bereglazov no comments were made so far, as he wasn't a realistic candidate for the Olympics anyway.