Pharmac is urging patients who are taking a cholestrol lowering drug with possible links to cancer, not to stop taking it, but to talk to their doctor.
Almost 6,000 New Zealanders use the drug Exetimibe, which is at the centre of international research controversy over whether it is linked to cancer, and whether it is effective.
In New Zealand, Exetimibe is funded by the drug-buying agency Pharmac and used in combination with another drug, Vytorin.
The latest issue of the New England Journal of Medicine contains an analysis of interim data from three trials of the drug.
One of the trials found the combined drugs had no impact on cardiovascular health in the patients taking it, and that there was an unexpected finding of a higher incidence of several cancers among the users.
Phamac's medical director Dr Peter Moodie admits the trial's findings were unexpected, but said it only involved patients with a particular type of heart disease.
Dr Moodie says people should not stop taking the drug, but should discuss the issue with their doctor.
He says it is possible that the benefits of the drug outweigh any risks, depending on the individual's cholesterol level.
Dr Moodie says the number of people taking the drug is small compared to the 300,000 taking statins, another class of cholestrol lowering drugs.