Diabetes NZ is concerned the price of a new blood-sugar testing method will prove too expensive for some unless the device receives funding from Pharmac.
The test, which was recently approved in New Zealand, involves wearing a small sensor on the upper arm which is scanned to get a glucose reading.
The scanner and sensors costs about $100 before shipping, but the sensor lasts only two weeks before needing to be replaced.
Diabetes NZ president Deborah Connor said while the technology was fantastic, the price attached would mean a lot of people could miss out.
"What it is going to do is make it a little bit prohibitive for a number of people, which kind of increases the inequities in our health system, yet again."
Diabetes is New Zealand's largest growing health issue, according to the Ministry of Health.
The Ministry of Health estimated more than 257,000 New Zealanders had diabetes and an additional 100,000 people were living with it undiagnosed.
Last year, government drug-buying agency Pharmac spent $13 million on funding for blood-glucose test strips for the finger-prick method, but at the moment it does not fund the sensor test.
Pharmac's website said anybody was able to make a funding application, though applications were assessed in bulk every three months.
Ms Connor said Diabetes NZ would assist New Zealanders lobbying for funding for the test.
"There's a big feeling out in the [diabetes] community that it needs to be something that's made available to everybody, not just those who can afford it."
University of Otago Associate Professor Jeremy Krebs said it could be difficult for people with diabetes to manage their blood glucose levels using the finger-prick test.
Associate Professor Krebs said the new technology would make a positive difference to people who struggled to test their glucose levels frequently.
"Whilst finger-prick testing can give them this information, it is often difficult to do this regularly, particularly in public situations," he said.
He also hoped the new technology would be funded by Pharmac.