Party pill retailers will be asked by the Ministry of Health to stop selling some new generation pills, following reports they have made some users sick.
Four people were admitted to Waikato Hospital after reportedly consuming large quantities of the substance dimethylamylamine or DMAA.
The Ministry says while party pills containing DMAA are not considered a significant health risk, it is concerned about the availability of the substance.
The Ministry says it is issuing a request to retailers, through public health units, to recall the powered form of DMAA.
The expert advisory committee on drugs is set to consider next month whether to include DMAA under the Misuse of Drugs legislation.
The Associate Minister of Health says changing the onus of proof on party pills is the only way to stop the party pill trade.
Jim Anderton says he's asked the Law Commission, which is reviewing the Misuse of Drugs Act, to look at the possibility of changing the onus of proof.
The Drug Foundation's executive director Ross Bell says the latest situation shows better regulations are needed.
"We're in the same situation we were when BZP first hit the market. There are no controls, no regulations around these substances," he said.
"The regulators are going to have to play catch-up and the chemists in the industry will always stay one step ahead," he said.
Mr Bell said the foundation would like to see age restrictions and accurate ingredient labelling.