One person has died and five others have been hospitalised in Wellington following suspected overdoses involving GHB in recent days.
The woman died at Woofingtons, a castle-like mansion in Wellington, after she consumed GHB from a bottle.
Misidentified substance found
A drug checking service identified at least one substance being sold as GHB that was actually 14BD, a related but distinct compound.
Jason George, national harm reduction lead at DISC Trust, said over the past week a couple of G-type substances arrived at the clinic, with at least one sample expected to be GHB testing as 14BD instead.
Three G-type substances exist: GHB, GBL and 14BD. George said one G-type drug can be sold in place of another on the market.
George said the misidentification posed risks because 14BD has a delayed onset. "Then it comes on a bit later and ends up being stronger than intended and people can accidentally overdose or take a bit more than they wanted to," he said.
Narrow margin for error
George said the difference between a safe and dangerous dose could be as small as tenths of a millilitre.
The gap between "having a good time" and "having a really bad time" was extremely narrow with G-type substances, he said.
George said when users believed they were taking one substance but had taken something different, they could assume the drug was not working and take more to achieve the desired outcome.
Testing urged
George said getting drugs tested could reduce overdoses.
"If you haven't had it checked, there's really no way of knowing that it's what it was sold to you as, so we really recommend coming into a drug checking service," he said.