Sellers of party pills have two weeks to clear their stocks before benzylpiperazine (BZP) is outlawed.
Parliament passed a bill last night banning the active ingredient from April 1 and classifying BZP as a class C drug - the same as cannabis.
Opposition parties branded the bill's sponsor, Associate Health Minister Jim Anderton, a "killjoy" and a "Muldoon Mini Me" for not allowing enough time to adjust.
Pill manufacturers say the law will drive users to more serious drugs such as ecstasy and alcohol.
The Misuse of Drugs (Classification of BZP) Amendment Act, effective from April 1, passed by 109 votes to 11 with the Green, Maori and ACT parties opposing.
An amnesty for those with pills for personal use will stretch for six months.
Mr Anderton had hoped to have the bill passed by December 18, but it was lost in the Christmas rush.
Green MP Metiria Turei said providers were not being given time to comply with the law, because they had to reconfigure businesses and in some cases lay off staff. She had tried, but failed, to extend the period.
Maori MP Hone Harawira said it was ridiculous to ban the pills when tobacco and alcohol remained legal. There was not enough evidence behind the ban.
Associate Health Minister Damien O'Connor denied there had been insufficient warning of the ban. Originally the bill was expected to pass last year, so the industry had warning well in advance.
Matt Bowden, chairman of the Social Tonics Association, said the industry had suffered from the vacillations of government.
Some had recalled stock for the proposed December ban, and others were now left with stock they could not sell.
"There's no talk of any kind of compensation. The feeling we get is it's the businesses' bad luck."
- With NZPA
- The Dominion Post
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