Distraction and lots of love, and in no time the E collar will be off. DO not even consider taking it off for a bit. Understand his frustration and go with it. Imagine yourself being in his positon. And go from there.
Yeah, the best thing to do is keep him distracted. It isnt good to give him medications because of the collar. There isnt an animal alive that likes the E collars. So, if you play with him, pet him, and give him loves that will help a lot.