The Commerce Commission is taking a Nelson pharmacy to court for price fixing.
It's accusing Prices Pharmacy 2011 Limited of charging $6, rather than $5, to dispense fully-funded prescription medicine in May of 2016.
The pharmacy also got its competition to agree to the price hike.
It's alleged the agreement was initiated by Prices Pharmacy at a meeting of Nelson pharmacy owners in April 2016, but the practice stopped when pharmacies started getting extra funding the following month.
Pharmacies had been warned about this twice before, in 2004 and 2014.
No date has yet been set for the hearing.