At Auckland University, neuropsychopharmacologist Dr Suresh Muthukumaraswamy is working to finish off approval for a historic LSD microdosing experiment - here in New Zealand.

His research could change lives, science, and how we treat psychedelics. Dr Muthukumaraswamy sat down with Newshub to discuss his work.

Psychedelic research flourished in the 1950s and 1960s, before concerns about LSD's recreational usage - and the overenthusiasm of some researchers - led to a legal crackdown.

But now the field is flourishing again as part of a psychedelic renaissance, with researchers exploring how psychedelics and empathogens could help treat mental health issues such as PTSD, addiction and clinical depression.

LSD works by binding to serotonin receptors in the brain, changing the electrical signalling and resulting in the hallucinogenic effects. While it is a Class A drug - the same as cocaine, heroin and methamphetamine - it has one of the lowest rates of harm for a drug and isn't considered to be addictive.

What is microdosing?

Microdosing involves giving people very small amounts of psychedelics, not enough to experience a perceptual difference but enough to cause a slight elevation in mood.

"Back in the 60s and onwards the focus was always a really large transformative doses where you take this one big dose… and have this profound psychological experience," Dr Muthukumaraswamy told Newshub.

"Then this microdosing phenomena kind of emerged with the publication of Jim Fadiman's book in 2011. What was happening in this kind of underground culture was people were starting to take very small doses of LSD or psilocybin, about a tenth of what you would have to have a tripping effect.

"They were taking it every second or third day, and they claimed that they can experience many of the positive effects, even some of the more long-term positive effects from taking these drugs, but actually only in very small doses."