About a million paracetamol tablets are dispensed every day, requiring two shipping containers to be imported every month.
Stocks are running low and new supplies are not expected until the new year.
A month ago, drug-buying agency Pharmac wrote to the country’s pharmacists instructing them to place restrictions on the way the drug was dispensed.
Pharmac director of operations Lisa Williams said the shortage was because of issues at overseas manufacturing plants.
A fire at one plant caused production problems of one of the active ingredients in paracetamol, she said.
‘‘That means all finished product manufacturers of paracetamol have been finding difficulties getting access to the active ingredient.’’
Restrictions mean patients who experienced acute pain can receive up to a 100 tablets at a time — about 12 days’ worth.
Those with chronic illness can get up to 240 tablets, about a month’s supply.
The restriction applies only to paracetamol bought on prescription. It is still possible to buy the drug off the shelf at a chemist or supermarket
Pharmacists such as Melina Holmes, who owns a Unichem Pharmacy in Whanganui, said since the restrictions came into place, the amount of pharmacy-dispensed paracetamol had dropped by about two-thirds.
She said such restrictions affected both pharmacists and the public.
She said the issue with paracetamol tablets came after restrictions on paracetamol liquid and ibuprofene tablets had just been lifted.
Ms Holmes, who has been a pharmacist for 20 years, said it was part of a worrying trend, with the number of restrictions seemingly on the rise.
Ms Williams said Pharmac has also begun funding an alternative, although that, too, was in limited supply.
She thought it was unlikely the country would run out.
‘‘There’s lots of other pain-management medicines that could be used, that would be what doctors would need to consider prescribing.’’
