A Cambridge University student died after he and his girlfriend bought a legal high from the internet months before it was outlawed, an inquest heard on Monday.

Thomas Millward, a first-year engineer, suffered an “unsurvivable” head injury after falling down several flight of steps at Girton College, Cambridge, on 6 March last year.

Mr Millward, 19, had been intoxicated on the legal-high “1P LSD” , which is a copycat version of the psychedelic drug LSD or “acid”.

He was taken to Addenbrooke’s Hospital shortly after 9.30pm, where doctors declared him brain dead.

New psychoactive substances such as 1-Propionyl-lysergic acid diethylamide, nicknamed 1P LSD, have grown in popularity in recent years due to their price and availability on the dark web.

While it was outlawed in May 2016 along with thousands of new synthetic drugs under the Psychoactive Substances Act, dozens of outlets operating outside of the UK continue to sell it online.