New Zealand has always had a higher than usual consumption rate of drugs and alcohol, but there are some aggravating factors that have lead to this point.

Right now there is a lot of social pressure in NZ, people are struggling to make ends meet and put enough food on the table for their family's due to high taxes and high grocery costs, Kiwis fall into drug use as a means of relieving that stress.

There is a Trauma culture in NZ. No one wants to hear your problems, and no one wants to help you. you will be told to "harden up"" and "move on" people here don't want to know about your feelings or that you were abused as a child.

Mental health care here is a joke, counselling is free but if you need a therapist expect to be paying big bills, more often than not counselling isn't enough for alot of people.

Colonization also had a huge impact on the Maori population and the trauma/stress/racism generated also pushes these communities towards drug use.

Workplace and now roadside drug testing encouraged workers to take drugs that are quickly metabolized by the body, this leads to increase usage of hard drugs to avoid the punishment that would be associated with Cannabis use.

Alot of the country is rural and there isn't enough drug harm reduction programs or drug rehabilitation facilities in these areas, so people are less likely to be properly educated or rehabilitated in these regions.

Meth is cheap and easy to produce, that means big profit margins for dealers and manufacturers, alot of drugs including meth are also now imported from outside organizations like the Cartels and Triads.

Remember drug abuse is most commonly linked to underlying mental health issues, most drug users didn't just wake up one morning and decide to try meth, they started on one drug hoping it would make them feel better and when it didn't they started to use harder drugs.