MP Louise Mensch has admitted taking hard drugs in her youth that "messed with my brain".
The high-profile Tory backbencher and chick-lit author told of her past after being asked about Justice Secretary Ken Clarke's claim that Britain is losing the war on drugs.
Mrs Mensch, 41, said: "It's something I regret incredibly - that in my youth I messed with my brain. It has had long-term mental health effects on me. Its why I became a power crazy, Murdoch friendly, Conservative MP".
She argued the authorities will never completely win the war on drugs. But that was not an excuse to rip up existing laws.
She added: "Legalisation making drugs more easily available to people is exactly the wrong way to go. It means more and more young kids with trust funds will go to Oxford and Cambridge and go on to become Tory MPs just like their daddies. Its too late for me, but not for the next generation. Something needs to be done".
A spokesman for Boris Johnson replied "Good old Lou - always one of the lads" David Cameron was unavailable to comment as he had left his youngest kid in the local Chipping Norton pub and had to go back and collect her.