A Northland GP plans to monitor how many of his prescriptions are not collected now that the fee has gone up.
The cost of a prescription rose from $3 an item to $5 on 1 January.
Lance O'Sullivan, of Kaitaia, says even at $3, many of his patients second-guess which prescriptions they need and which ones they can safely leave behind.
Dr O'Sullivan says he and a local pharmacist are going to do their own cost-benefit survey of the effects of the fee increase.
"We're going to find out how may prescriptions I write and how many actually are collected and measure that against how many people of those ones that don't get collected end up in hospital."
Dr O'Sullivan says the fee increase is a false economy, because hospital care is far more expensive.
Meanwhile, the Pharmacy Guild wants to discourage pharmacies from absorbing the increase in the prescription fee.
A Christchurch pharmacy has said it will absorb the cost, but the guild says that is not a long-term solution.
Pharmacy Guild president Karen Crisp says medicine is a cost-effective intervention, and sustainable solutions are needed to ensure that there are no barriers to prescriptions.
Ms Crisp believes it is not sustainable to have pharmacists making charitable donations.
The guild supports means-testing for prescriptions so low-income earners do not have to pay more, she says.