The Multi-Disciplinary Association for Psychedelic Studies describes ibogaine, sourced from the plant Tabernanthe iboga, which originates in Africa, as a psychoactive alkaloid, a mild stimulant when taken in small doses but capable of inducing a profound psychedelic state in larger doses.
In 2009, MedSafe approved it as a prescription medicine only, but NZ Drug Foundation executive director Ross Bell said his organisation had concerns about its use, with only two places at each end of the country using it as a drug treatment.
"We have always urged caution on the use of ibogaine, due to lack of clinical evidence," he said.
"It was allowed by MedSafe, but after reading the decision it seems that that was just to stop it becoming another legal high.
"It's been described as this miracle cure but there isn't the medical literature around its effectiveness. There are reports of it leading to deaths, which raised our concern. I hope our concerns haven't been proved right with this case."
Mr Bell said the foundation would call on The Government to restrict those able to prescribe ibogaine treatment to psychiatrists and addiction medicine specialists.
Last year, Dr van Dorp and his wife, Anah, claimed remarkable success with iboga (Kaitaia leads with 'miracle drug,' Northland Age, June 7, 2012).
They said a single treatment typically caused a massive reduction in the symptoms of drug withdrawal, allowing relatively painless detoxification, and a markedly reduced desire to use drugs for between a week and several months.
Mrs van Dorp said the drug had long been used by tribes in the Congo and had been used in the west for the treatment of drug addiction for the last 50 years, although it remained illegal in many countries, including the US, Canada and Australia.
At that stage, the clinic had treated 20 people, with a 95 per cent success rate.
Clients were treated one at a time and were constantly monitored.