An inhalable caffeine fix the size of a tube of lipstick has become the latest energy supplement to hit the market.

Created by Harvard professor David Edwards, the AeroShot delivers 100 milligrams of caffeine powder in an inhaler, giving users an instant fix equivalent to that of a large cup of coffee.

But experts have questioned the new product's potential health implications, and Democratic U.S. Senator Charles Schumer of New York wants the U.S. Food and Drug Administration to review AeroShot, saying he fears youngsters will use the inhaler as a club drug to drink to excess.

Edwards said AeroShot was not aimed at under-18s and was a safe alternative to coffee.

He said: Even with coffee--if you look at the reaction in Europe to coffee when it first appeared--there was quite a bit of hysteria.

So anything new, there's always some knee-jerk reaction that makes us believe 'Well, maybe it's not safe.'

So far AeroShot has been rolled out in New York, Boston and in France--where it is manufactured.

According to Edwards, the idea came to him after a conversation with French chef Thierry Marks in 2007, with the pair combing culinary expertise and Edwards' work on medical aerosols.

The result of that conversation was Breathable Foods, whose first venture was an inhalable chocolate called Le Whif.

According to Breathable Foods, the AeroShot is not intended to replace coffee but is meant to give people with active lifestyles access to their caffeine fix.