The 18-year-old was taken to hospital after collapsing in a street in Bexley, late on Saturday. He died two hours later.
A teenager believed to have taken so-called laughing gas at a party in south-east London has died, police said today.
The 18-year-old was taken to hospital after collapsing in a street in Bexley, late on Saturday. He died two hours later.
The Metropolitan Police said he was believed to have been drinking alcohol as well as ingesting legal high nitrous oxide, also known as laughing gas.
Seventeen people in the UK died between 2006 and 2012 after taking the drug.
The teenager's next of kin have been informed.
"At this stage the death is being treated as unexplained pending the findings of the post-mortem," the BBC quoted a Met spokesman as saying.
The government plans to ban the sale of legal highs, which would include nitrous oxide.
The gas - inhaled using a balloon - can make people feel relaxed, euphoric and giggly, which has led to its nickname.
But abusing nitrous oxide can lead to oxygen deprivation, resulting in loss of blood pressure, fainting and even heart attacks.
It is not illegal to be in possession of the gas, although it is prohibited from being sold in England and Wales to under-18s if there is a risk they will inhale it.