Man, either he was getting those directly from a doctor with a shady reputation, or he was going to different doctors and definitely getting them filled at different pharmacies. Where I work (Walgreens), I'm pretty sure all the "drug interaction" red flags would pop up if he tried to get that cocktail refilled at one time. As far as the "accidental overdose," someone had an excellent post earlier in this thread about how that happened to them. In this case, I think given his predisposition to addictions (heroin), once your body develops a tolerance, you need more to do the trick. If he was self-dosing, the whole thing would have been a guess on his part, so I can easily see how this could be accidental. He obviously should have sought help before it got to this point.