The Government is seeking advice on whether to make possession of laughing gas a crime.
The Home Office has asked the independent Advisory Council on the Misuse of Drugs (ACMD) to review the harm caused by nitrous oxide.
It is acting following what it calls a “concerning” rise in use among young people, with the substance the second most-used drug among UK 16 to 24-year-olds.
Drugs experts said the move was “completely pointless” and a “waste of time”.
More than half a million people aged 16-24 (8.7 per cent ) in England and Wales used the drug in 2019-20, according to the Crime Survey.
According to the Office for National Statistics, there have been 36 deaths in Great Britain associated with nitrous oxide between 2001 and 2016.
The sale of nitrous oxide for its psychoactive effects is illegal but it is not a crime to possess the drug.
The Government is concerned this is a “significant factor” in its increasing use.
The ACMD’s assessment could also recommend more education for young people or tougher punishment for those who supply the drug to children.
Home Secretary Priti Patel said: “Misusing drugs can have a devastating impact on lives and communities – we are determined to do all we can to address this issue and protect the futures of our children and young people.
“Should the expert ACMD recommend further restrictions on this drug, we stand ready to take tough action.”
The ACMD last reviewed nitrous oxide six years ago, concluding it did not seem to warrant control under the Misuse of Drugs Act 1971.
Prolonged use of nitrous oxide can cause vitamin B12 deficiency, anaemia and nerve damage.
The drug is typically used by being released into balloons from small silver cannisters and inhaled, giving temporary feelings of relaxation and euphoria.
It is also used medically as an anaesthetic, given for instance to women in labour.
The former ACMD chairman, David Nutt, who was sacked in 2009 after claiming that ecstasy and LSD were less dangerous than alcohol, called the move a “gimmick”.
The Professor of Neuropsychopharmacology at Imperial College London, and founder of the charity Drug Science, said it is “completely symptomatic of the utterly blinkered perspective that this Government has on drugs”.
He told the PA news agency: “This is completely pointless, an utter distraction, this is pretence of doing something about drug problems, but focusing on a drug that has very, very little harm – way less harm than alcohol – and they should be investing their money on people who are dying of drugs like fentanyl and heroin”.
Another leading drugs expert called the move a “waste of time” and said criminalising possession “would likely lead to illicit sales”.
Adam Winstock, a consultant psychiatrist and addiction medicine specialist, told PA: “Asking for evidence is great but the ACMD advice comes framed by the current Home Secretary’s preconceived notion that a problem related to drug use can be successfully addressed by making something illegal.
“This is palpably and evidentially false. But making a drug with minimal risk to most users illegal will add the risk of criminality to all.”
Prof Winstock, founder of the Global Drug Survey, said nitrous oxide is “very safe” compared to other drugs, with the risk of accidental harm low but increased when consumed with other substances.
The risk of nerve damage is “real and significant”, he said, with a study on 16,000 users showing just over 3 per cent reported symptoms consistent with nerve damage.
He continued: “That is a worry. But avoidable.
“Smart education, not blunt regulation, is required.”