Scientists looked at 24 studies into modafinil, a drug which promotes wakefulness and is used to treat narcolepsy, excessive sleepiness and sleep disorders resulting from shift work.
They concluded the drug can improve decision making, problem solving and may even make people think more creatively.
Researchers said the drug is safe when taken on a short-term basis, but acknowledged there is limited data available on the effects of long-term use.
“Modafinil can and does enhance some cognitive functions,” said Dr Ruairidh Battleday of Oxford University.
“For the first time, we have a cognitive enhancer that appears not to have significant detrimental cognitive, emotional, or physical side effects.
“This means that it is time for a wider societal debate on how to integrate and regulate cognitive enhancement. The ethical exploration is a huge and important goal for the near future: one that both scientists, politicians, and the public need to be involved in.”
“Modafinil is the first real example of a smart drug which can genuinely help, for example, with exam preparation,” said Guy Goodwin.
“Previous ethical discussion of such agents has tended to assume extravagant effects before it was clear that there were any. If correct, the present update means the ethical debate is real: how should we classify, condone or condemn a drug that improves human performance in the absence of pre-existing cognitive impairment?”
A survey by Oxford University student newspaper The Tab found one in four students took Modafinil.
Similar usage figures have been reported for universities in Newcastle and Leeds, while a fifth of students at Imperial, Sheffield, Nottingham and Manchester also admitted using the drug.
It has also been used by US Air Force pilots to stay alert during long distance flights.