A CORONER issued a warning to the NHS over the death of a woman from laughing gas. Ellen Mercer , 24, suffered a blood clot after inhaling two to three large bottles every day. An inquest in April heard sustained nitrous oxide abuse , which left her unable to walk, contributed to her death.

The student, from Gerrards Cross, Bucks, died after 24 hours in a hospital emergency department without any formal blood clot risk assessment. Heidi Connor, senior coroner for Berkshire, voiced concern that those assessments take place only within 24 hours of admission to a ward. In a prevention of future deaths report, she said long A&E waits before a patient is admitted are not factored in.

Pals called Ellen — who died in February last year — “truly beautiful and a gentle soul”. Last month, Ellen's mum issue a heartbreaking warning after her daughter's death. Sharon Cook told The Sun: "If there is one more life that could be saved from your report, then it is all worth it.

"Ellen did not know the dangers of this drug at the time. The message was: it was legal and therefore it's safe. "The risks of nitrous weren't publicised, now everyone can see the risks involved - just don't do it.

" NITROUS oxide - also known as laughing gas or hippy crack - was recently made a Class C due to the dangers associated with the drug. It can cause a range of health issues and in some cases can even be fatal. Some common side effects from inhaling the gas are dizziness , nausea , disorientation, loss.