When john is on meds his brain to mouth filter shuts down.
oneday he's on meds and can't stay alone at the house, and mrs hudson isn't their to watch him so sherlock has to take him to a crime scene. Johns mad and annoyed and complaining the whole time how he wants to go home and how this is boring and that they should do somethign fun. The yard needs sherlock to solve the case so john deducts the whole crime scene giving the correct cause of death and who the murder is and acts like it's nothing.

"there it's solved now can we go back home please. I want pudding"