i've heard of morphine hallucinations, but not on any opioids, morphine is one of the natural ones (opiates)

hydro- and oxycodone are synthetic (opioids) and you'd have to overdose really bad to hallucinate, and i guarantee you'd puke it up first, synthetics are fine-tuned like that on purpose, the only side effect they can't really minimize with the effective ones is the addiction