Patients could benefit from cheaper prescriptions after the competition regulator warned health boards and pharmacies against a "no discounting" clause in their service agreement.
The Commerce Commission launched an investigation last year into whether the 2012 agreement between every District Health Board (DHB) and pharmacy in the country was in breach of competition laws.
It found two clauses in the agreement were likely to have breached the Commerce Act because they effectively prohibited pharmacies from waiving or discounting the $5 co-payment that patients contribute towards each prescription item.
The government subsidises the cost of pharmaceuticals but patients themselves contribute a co-payment, the cost of which is set by the Government.
The Commerce Commission's decision means pharmacies are now free to discount or waive the co-payment amount, which could promote competition to the benefit of patients.