Woman critical and five others in hospital after GHB overdoses in Melbourne

Six people were taken to hospital in Melbourne overnight after overdosing on what is believed to be the party drug GHB.

Emergency services treated two women and four men aged in their late teens and early 20s after they fell ill in the nightclub precinct of King Street and Little Bourke Street.

All six people were taken to hospital in the early hours of today and one of the women is fighting for her life at St Vincent's Hospital.

Three of the other party-goers were transported to hospital in a serious condition, including a teenage boy, while the remaining two are reportedly in a stable condition.

It is believed at least some of the overdoses occurred outside King Street nightclub Inflation.

Ambulance Victoria executive director of emergency operations Mick Stephenson said the incidents were a common problem for paramedics.

“Last night was not out of the ordinary,” he said.

Mr Stephenson said GHB (gamma hydroxybutyrate), unlike some other drugs, makes patients behave unpredictably.

“Patients’ conscious state tends to fluctuate quite markedly and their vital signs, so their blood pressure and heart rate and so on also fluctuate quite markedly,” he said.

“We don’t see that in most other illicit drug use”.

Deputy Commissioner Rick Nugent highlighted the dangers of GHB, saying police “don’t know exactly what goes into it”.

Mr Nugent said users sometimes took double-doses of a precursor that mimicked the effect of GHB, believing the first dose hadn't worked when in fact it simply took longer to take effect.

He also said the risk of overdose increased when users mixed GHB with other drugs or alcohol.

Police said a 22-year-old Hawthorn man was arrested on King Street just after 3.30am and will be charged with drug related offences.

The arrest is not believed to be linked to the overdoses.

With AAP.