You know that sleepyness where you literally cannot keep your eyes open and keep dozing off? That’s what an opioid overdose is like. If you gave someone a bunch of morphine, they’d fall asleep and soon after stop breathing.

Some people experience different levels of nausea from different kinds of opioids, so some level of discomfort will exist in some percent of the population without either testing out the different opioids on the prisoner or giving them an anti-nausea drug.