One of our officers once responded when a worker at a local care facility took a patch intended for a patient and went to chewing it in a supply closet.One of the most used drugs in surgical anesthesia. As a hospital pharmacist for nearly 50 years no idea how much I have dispensed. It was all highly controlled and documented. We even used the topical patches for post surgery in some cases, and doing relief pharmacy even see some used for cronic conditions, although use of those items has dropped off in the last few years. One problem with it was some nurses, and it seemed to be more nurses than other groups would take used patches an cut them open to get at the remaining fentanyl , we finally had to institued a policy for witnessed disposal.