Dragons feeding monkeys

I have never read Game of Thrones, but last season on that show two captive dragons fully scarfed down a flaming dude. They peeled him back like pepperoni, and the shock set me to crunching numbers. If three teenage dragons that flew amok toasting shepherd children were your charge, how would you bring them to heel?
The answer, dark and cruel though it may be, is clearly the only way to leverage the power of these airborne death lizards: dragon crack.
So far the show has presented napalm (“wildfire”) and opiates (“milk of the poppy”). Are medieval stimulants really such a stretch?
Imagine some bent and frazzled maester emerging from his lab holding aloft the product of his marathon toil in shaking hands. He would hasten to an audience with Daenerys Targaryen, whose eyes would narrow as she listened.
I envision the pipe as a permanent military facility set into a large hill. It’s manned by a squad of 50, “The Devil’s Bellows,” who bring the gear up through tunnels from the scullery deep below and stoke an undying fire in shifts like oarsmen.
When the winged fiends alight, having duly roasted an army, a cry goes up and all hands man stations. The chamber is filled with bundles of blue-hued crystal and the growing flame unfurls huge curtains of smoke.
Weary and gaunt, the dragons know the drill. They twitch and cough until the first column of smoke is hoovered up. Then they wheeze with delight and take off, haphazardly zagging their way to a distant eyre to play dragon word games and count their digits until the lever of addiction drives them once again to war.