124.417  Imitation controlled substances — exceptions.
  It is not unlawful under this chapter for a person registered under section 124.302, to manufacture, deliver, or possess with the intent to manufacture or deliver, or to act with, one or more other persons to manufacture, deliver, or possess with the intent to manufacture or deliver an imitation controlled substance for use as a placebo by a registered practitioner in the course of professional practice or research. 
2017 Acts, ch 145, §15