National has released figures showing a stark rise in the number of people being hospitalised with synthetic drug poisoning.
But the numbers fall far short of those ending in up hospital due to alcohol consumption.
According to Ministry of Health figures the party obtained under the Official Information Act, in the past year 84 people have been hospitalised due to "poisoning by other psychotropic drugs, not elsewhere classified", of which most are synthetic cannabis.
Ministry of Health data shows 50 under-14-year-olds have been hospitalised in the past five years.
That's more than double the number of those taken to hospital for synthetic cannabis poisoning during the same period.
Public Health Professor Max Abbott says "a growing brain and cannabis is certainly not a good combination, and we need to do everything we can to prevent that".
"One needs to be vigilant about younger people. Cannabis is not something that people in their teens should be using."
Mr Abbott says the figures for psychoactive substance hospitalisations are low, but it's still a concern and the numbers could escalate.
There are two approaches to this, he says.
"One is reducing supply and the other is reducing demand."
National MP Simeon Brown says "even one child is one too many".
"I imagine the majority of that would be they are being exposed to adults who are consuming the drug around them."
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The previous year there were 46 hospitalisations, and the year before that just 13. In the 2015/16 year - when the Psychoactive Substances Act was introduced - there were only 10.
Mr Brown says it shows the Act needs "fixing", with tougher penalties. He has a Private Member's Bill to raise the maximum penalty for supply from two years to 14 years.
"The correlation is clear between the large increases in hospital admissions and manufacturers of synthetic drugs continually coming up with deadlier strains," he said.
"Labour and the Greens continue to ignore the seriousness of this issue, and if it wasn't for New Zealand First's continued support of my Bill these numbers would likely rise again."
But the figures also show that five years ago there were 72 hospitalisations - only a dozen below the latest statistic.
And each year more than 4000 Kiwis end up in hospital thanks to their alcohol consumption, and - according to the official statistics - about 180 die. University of Otago Chair in Preventive and Social Medicine Professor Jennie Connor told Newshub in June that's a "vast under-representation" and the true figure is probably closer to 800.
The Ministry of Health figures also show 79 Kiwis were hospitalised in the recent year due to natural cannabis poisoning, out of about 445,000 adult users. That's up on the past two years (74 and 73), but below figures recorded in 2014/15 (84).
There have been at least 45 deaths linked to synthetic drugs since mid-last year. No one has ever died of a cannabis overdose.
Newshub has contacted the NZ Drug Foundation for comment.