Opioids can be taken in a number of ways.
If the person can swallow, all can be given by mouth.
If the person can no longer swallow, some medications can be given intravenously, and some by injection beneath the skin.
A compounding pharmacist can mix an opioid with a gel to deliver it topically, through the skin.
Some formulations can be delivered by patch or through a cheek film that crosses the mucous membranes in the mouth.