NZ First has accused Pharmac of treating vulnerable people like "lab rats" after the Government's drug buying agency switched to a sole provider for diabetes equipment.
Pharmac yesterday announced diabetics would be limited to three types of subsidised glucose-testing meters, which along with testing strips, would be sourced from Korean supplier CareSens.
The move will save the Government $10 million which it says will be reinvested into other medical devices and medicines.
NZ First health spokeswoman Barbara Stewart said the new meters were "untrusted and unknown".
The change would have a dire effect on the elderly who generally struggled with changes in technology and might forgo testing their blood-sugar levels, she warned.
New Zealand couldn't afford to treat its vulnerable like lab rats, she said.
"If the Government was serious about tackling the serious issue of diabetes, it would help diabetics rather than make life more difficult for them."
The Government and Pharmac cared more about money than they did about people, Stewart said.
"We've spoken with doctors, health professionals and diabetics and they all say that this is purely an economic exercise aimed at saving a few dollars rather than doing what is best for those New Zealanders suffering from diabetes."
Diabetes New Zealand has said relying on a sole supplier was an "untenable risk".
However, Pharmac chief executive Steffan Crausaz said the agency would have at least four months' stock of testing strips to minimise the risk of running out.
The changes were heavily critcised when they were announced earlier this year and led to protest marches in Wellington and Auckland. The Government received more than 3000 submissions about the move.
Funding changes to the meters and test strips will be phased in over six months, beginning in September.
There will be a nationwide meter swap and education campaign involving pharmacists and clinicians, as well as community and consumer groups.
Diabetes New Zealand estimates 200,000 New Zealanders are affected by diabetes.
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