The Bristol University professor sacked as the Government's drugs czar for saying ecstasy was no worse than alcohol, is developing a drink that he claims will give a similar kick to spirits but without harmful effects.

The liquid shot would give the same lift as a few drinks after work. But those enjoying its benefits could then take an "antidote" to sober them up before driving home. There would be no hangover and no damage to the liver.

Professor David Nutt, chairman of the government's Advisory Council on the Misuse of Drugs until he was dismissed last year, is developing his synthetic alcohol at Imperial College London.

He said the "Nutt slammer" could be on the market by the end of 2012 if money is available for clinical trials. It would provide all the pleasures of alcohol with no downsides.

It would need licensing, however, and the trials could cost as much as £10 million. It could also pose serious questions for lawmakers over whether it is a safe drug to take before getting behind the wheel.

Professor Nutt, a neuropsychopharmacologist nicknamed the Nutty Professor by critics, believes his alternative could cut the number of deaths from alcohol poisoning and liver disease and help to reduce stomach ulcers and heart disease.

It is based on drugs known as benzodiazepines or "benzos", which include valium and temazepam. The prototype is in the form of a tablet or injection.

Professor Nutt envisages it being marketed as a tasteless liquid shot to mix with a fruity drink. The synthetic alcohol works on the nerves in the brain that make people feel relaxed. Rather than getting drunk, they would stay in a pleasant state of mild inebriation.

Professor Nutt claims there are no risks associated with long-term use of benzos. Other doctors disagree and point to people with addictions to drugs, including 1.5m people in the UK believed to be addicted to tranquillisers.