Diabetics outraged at the quality of new blood testing meters say it is only a matter of time before they cause deaths.
The Korean-made CareSens meters, introduced by Pharmac in March, have been dubbed "CrapSense" meters by hundreds of type 1 diabetics who say the inaccurate readings they produce are endangering lives.
Pharmac opted to cut funding for all other meters and strips to make way for the cheaper CareSens products at a saving of around $10 million following a consultation period last year.
Patients can still use their old meters but at their own cost.
North Shore teenagers Harriett Maire, 18, and Miriam Scott, 15, both type 1 diabetics, have joined a petition to the Government to have the decision overturned.
The petition has gained almost 1800 signatures in less than a fortnight.
Both teens have said the new meters have failed them so often that they are now reluctant to use them.
Instead they have stockpiled the older testing strips so they can continue using their trusted old meters.
Miriam's mum Michelle Fitzsimons said she feared what would happen once the stockpile ran out.
"It is going to cost us around $50 a week to remain on the old meter. That's $50 I don't have but will find somehow because I will not endanger my daughter's life."
Ms Fitzsimons said the CareSens meter seemed to be affected by the cold climate while on holiday at Lake Tekapo.
The meter read four points above that of her daughter's old Accu-Chek meter.
Other photos of faulty readings have been posted on the Facebook page Stop Pharmac taking away the choices of people with diabetes!
Extremely high or low blood glucose levels can cause long term damage and even death if not treated immediately.
Examples of children suffering seizures and unconsciousness because of poor readings have also surfaced on Facebook.
"As parents it's terrifying, you just cannot trust it.
"The danger is if the CareSens reads 15, when in fact you are a seven, injecting insulin could make you go dangerously low and your life could be in danger," Ms Fitzsimons says.
Pharmaco is the sole supplier of CareSens equipment to New Zealand and has acknowledged the meters may not function in temperatures under 10 degrees or above 40 degrees Celsius.
It has advised users to warm up the meters before use by placing them close to their skin or by moving to a warmer area.
"When you're low time is of the essence. We just don't have time to hang around trying to warm the meter up under our armpits," Ms Fitzsimons said.
Pharmac's decision to switch suppliers is short sighted, she said.
"They've estimated it costs around $1 million to support a diabetic throughout their lifetime.
"Yes, this may be saving money in the short term but because the meters are so unreliable they'll end up with more people in hospital."
The threat of inaccurate readings was a constant stress, Harriett said.
"When you're low you know it. We have all grown to know our own bodies. But when the machine is telling you different then you start second guessing yourself and it is quite a disconcerting feeling."
CareSens products, manufactured in three separate locations in South Korea, are compliant with ISO standards and have been evaluated by the Christchurch Diabetes Centre. It says 80,000 CareSens meters have so far been distributed throughout New Zealand.