The Green Party's three-year campaign to allow cannabis to be used for medicinal purposes came to grief in Parliament on Wednesday night.
Their bill failed on its first reading, voted down 86-34 on a conscience vote.
Its promoter, Metiria Turei, pleaded with MPs to let it through so it could go to the health select committee which could hear evidence of how cannabis eased the suffering of seriously ill people.
"Many people already use it and they live in real fear of the law," she said.
"Sick and vulnerable New Zealanders are being jailed ... let MPs hear their stories, let these people have their say."
Under the bill, seriously ill people would be able to apply for a cannabis card, issued on a doctor's authority and registered with the police, which would allow them to grow small amounts of it.
Turei said they didn't have to smoke it, they could use it in other ways to help relieve their pain such as making tea with it or using it as oil to rub into their limbs.
MPs who spoke in the debate said they knew Turei was sincere about relieving suffering but those who opposed the bill listed numerous problems they had with it.
National MP Jonathan Coleman, a doctor, said it would bring cannabis into mainstream society.
"You can't make out it is a good thing, we need less drugs in society," he said.
"We would be sending a signal that it's okay."
He said doctors would be swamped with demands for cannabis cards from people insisting they were seriously ill and needed it for pain relief.
Coleman, and other MPs, said there were prescription drugs available which used THC, the active ingredient in cannabis.
Labour's health spokeswoman, Ruth Dyson, said the prescription drugs were "horrifically expensive" and although there were problems with the bill the health select committee should have a chance to consider it.
The bill would have amended the Misuse of Drugs Act and it had been on Parliament's order paper for three years.
Medicinal use of cannabis is currently legal in 13 US states, Canada, Spain, Germany and the Netherlands.