Don't see what happening? I gave the two extremes, you don't see either happening? Out of all possibilities, I see the current situation continuing on as the LEAST likely...
Or the cuts potentiate the opiate, such as benzos and ketamine, which are not more powerful, but will greatly potentiate heroin.
These mixes can easily cause the user to fall out. The result is a lack of lack of oxygen in the brain and can easily cause brain damage/death. Although I'm not sure if that would technically be an "overdose", per se, but I'm sure the news would claim it was.
And please DO NOT TRY THIS, even if you have a dose of heroin that's probably not enough to get you high. I've already known one person to die and another person who suffered permanent brain damage with these combinations. We don't need anyone else on Black Light.