Stephen Hawking Says Smart Pill Is Proven To Double IQ.
First of all, IQ doesn't work that way. Intelligence quotient is determined by taking a group of tests. Your performance on the tests, and hence your score, can improve, but not dramatically enough to double, such as going from 100 to 200, which would be a jump from average to a high genius level. No pill will change your brain in a way that makes this possible.(And all this is ignoring things like whether the IQ test is a legitimate way to determine intelligence, what determines intelligence, and so on.)
As for Stephen Hawking, he is a brilliant theoretical physicist. He is not a doctor, a chemist, or a biologist. Being really smart about one area does not mean you always know what you're talking about regarding anything else. I'd no more go to Hawking for medical advice or information on the latest studies of the brain than I'd go to a heart surgeon for the latest information on string theory.
Of course it's a pretty reasonable guess that Stephen Hawking said nothing of the sort. But using the name of someone everyone knows is really smart tends to work better when you're trying to find new suckers to buy dubious medical products.