I've just performed this home test: Here are the results: The instructions for interpretation are a bit brief. So, this saying: NO morphine, opiates NO amphetamines YES methamphetamines YES (borderline) cocaine YES pot He admits having done coke somewhat regularly until a week ago, so that result is unsurprising right? It will show positive with long-term heavy use. He admits to having pot, no trouble there. But the methamphetamines surprised even him. I'm guessing that's what the coke was cut with. Even he knows he's getting low-grade stuff. (Though if it were cut into the coke, why is it showing up so strongly, whereas the coke isn't quite so strong?) Any thoughts?