As OpiateKiller said, you should never, ever IM pills. The reason for this is that the binders and fillers are not water soluble, so despite efforts to filter it, you will end up with microscopic particles that you inject into your muscle. Even with drugs that dissolve totally, any little trace bit of foreign matter that gets in there will be injected into your muscle. This is actually more dangerous than IVing it, because the risk of abscess is very high. The only way you should even CONSIDER ever IMing non-sterile drugs is if you use a micron wheel filter, but even then, little particles can get through, and it is not safe.
The only drugs you should ever IM are drugs designed for injection that you get in sealed pharma vials. With these you can be sure they are 100% clean and you can keep the risk of abscess low. You do not want an abscess. best case scenario they are extremely painful, but once infection sets in, you can pretty quickly end up losing a limb or even dying.