A tribe in the jungle consider farting after every meal to be a sign of power, however the chief of the tribe finds it extremely difficult to fart.
His servant goes to the doctor and say "big chief, no fart" so the doctor gives him a pill
The next day the servant goes back to the doctor and says "big chief, still no fart" so the doctor gives him a big pill the size of his hand
On the third day the servant goes back and says "big cheif still not fart" so the doctor gives a pill the size of a football
The next day the servant comes back and says to the doctor "big fart,no chief!"