One of the conditions of CCW in my county specifies that ANY kind of prescription drug affecting perception or reflexes is verboten.
Ask youself: would I drive a vehicle under the influence. You can be DUI while on physician recommended dosages of meds. A blood test after an incident would put you in HOT water.
Also many LEOs, today, are trained to spot drug use by the dilation ot your pupils. You would be dead meat while giving an after-action report to a competent LEO.
DON'T DO IT! You would not drink a beer at the range while training. So, why would you consider popping a T-3 w/codeine and then go armed into harm's way. DON'T DO IT!
Be an example. A good example.
-William