Thousands of prescription pills were seized by Customs at the border during a worldwide crackdown on illegal and counterfeit medications being sold online.
Drug safety authority Medsafe is holding 298 suspicious packages, including 8774 tablets, following a week-long operation that ended on Tuesday.
The parcels were posted from 32 different countries and were stopped because they either contained prescription medicines, were not labelled or contained undeclared or hidden ingredients.
The most common source countries were India (79), United States (59) and China (30).
People importing the medicines have 30 days to prove it is legitimate by providing a valid doctor's prescription. If this doesn't happen, the medicines will be destroyed.
Medsafe compliance management manager Derek Fitzgerald warned people of the dangers of buying medicines online as they can be substandard, illegal or counterfeit.
One of the packages seized contained counterfeit medicine for erectile dysfunction.
Fitzgerald said anyone who intended to buy prescription medicines via the internet should speak to their doctor first and go through the right channels.
Medsafe discouraged people from obtaining medicine from overseas mail, he said.
It is illegal for a prescription medicine to be sold outside a pharmacy, but it can be imported for personal use if a New Zealand doctor has prescribed the medicine.
Pharmacy Guild chief executive Lee Hohaia cautioned people against shipping in their own prescription medicines as people could not be sure they were completely safe.
She said that, while online shopping was perceived to be cheaper and more convenient, prescription medicines should be dispensed by a pharmacist to minimise adverse side-effects and risks, which can change over time and with different illnesses.
"You can't just assume that you can go away and for the next 10 years buy these medicines online."
Common medicines seized during the operation were for weight loss, diabetes, heart and circulation and insomnia. Antibiotics were also prevalent.
"In this situation I would say that many of those medicines would be available in New Zealand and funded," Hohaia said.
Fitzgerald said unlabelled medicines were the most common products found during the operation, compared to last year when erectile dysfunction products were most prevalent.
He put this down to Viagra coming off patent and cheaper versions becoming available since then.
Medsafe investigates about 1000 parcels suspected of containing medicines each month and about 75 per cent are destroyed as people fail to provide the necessary documents.
Customs air cargo manager Cliff Russell said the volume of prescription medicine packages coming into the country had been steadily rising up until about 12 months ago, when it began to "level off".
Extra staff were brought into the International Mail Centre in Auckland to manually inspect packages or put them through an X-ray machine during the week-long Operation Pangea VI, which was led by Interpol and involved 99 countries.
- Fairfax Media
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