The Ministry of Health is being accused of acting outside the law by restricting some drugs from coming into New Zealand, when government scientists say they should be available through a doctor.
It's classified medical marijuana product Elixinolin as a class-B drug, so it needs to be signed off by Associate Minister Peter Dunne.
Nelson teenager Alex Renton was the first and last person it was signed off for.
But now government scientists are saying the extra layer of red tape shouldn't be necessary.
"We advise the Ministry of Health that in our consideration, CBD should be considered as a prescription medicine," said Institute of Environmental Science and Research scientist Kevan Walsh.
Cannabidiol, also known as CBD, is the active ingredient in Elixinol.
The Ministry considers this to pose a high or moderate risk because it has the same molecular formula as THC, or tetrahydrocannabinol, the so-called high in cannabis.
Scientists argue CBD has a different chemical formula, and there is no high.
Lawyer Sue Grey is threatening legal action unless the Ministry changes its position.
"I believe the Ministry of Health is acting illegally in blocking access to CBD. It's a recognised safe medicine overseas, it's used as a dietary supplement," said Ms Grey.
"There are many New Zealanders who will benefit from access to it and it's being blocked by the Ministry of Health, contrary to expert advice."
The Ministry of Health is now reviewing the legal status of CBD.
Australis recently relisted CBD from a controlled drug to a prescription only medicine.