Many New Zealanders are not getting free prescriptions they are entitled to and the most vulnerable are likely to be hardest hit when charges rise next year, researchers warn.
Most people pay $3 per medicine at the pharmacy, and after members of a family have paid for 20 prescription items in a year, all of them should be exempt from the charge.
But Pharmac data show 180,000 people pay for prescriptions after becoming exempt, costing them about $2.5 million a year.
A study into prescription use by researchers at Otago University and Wellington's Victoria University, led by Professor Pauline Norris, shows those affected are likely to include the country's most vulnerable people.
Using anonymous data from community pharmacy computers, researchers identified individuals who had more than 20 items dispensed in a year and found most were from socio-economically deprived areas.