A deadline has been set to remove from shelves medicines used by 78,000 people to treat chronic pain.
The Ministry of Health says Paradex tablets and Capadex capsules will be no longer available from 1 August.
A review by Medsafe found the drugs were no better at treating pain than paracetamol, but were dangerous in overdose or if taken with alcohol.
Medsafe spokesperson Stewart Jessamine says the deadline will give doctors time to transfer patients to a new medication.
Dr Jessamine says most patients will manage with just paracetamol, but some may need other treatment.
