Hong Kong on Friday added four substances to its list of dangerous drugs, a move which significantly increases the maximum punishments for people caught consuming, possessing, trafficking or manufacturing space oil.

Users and those found with the space oil drug now risk prison terms of up to seven years and a fine as high as HK$1 million, while manufacturers or traffickers of any of the substances involved – etomidate, metomidate, propoxate and isopropoxate – can be jailed for life and hit with HK$5 million in fines.

Previously, the maximum prison term for space oil, under prescription drug regulations, was two years.

Commissioner for Narcotics Kesson Lee said the tougher penalties will be a bigger deterrent.

"By listing the substances as dangerous drugs, we give greater powers to law enforcement agencies," Lee said on an RTHK programme.

"Officers can seize the proceeds of drug traffickers after applying to the courts. And if the traffickers had used young people for trafficking, we can also demand the court to pass heavier sentences."

The Community Drug Advisory Council said the increased penalties are helpful, but they won't completely stop people from supplying or using space oil.

"There will still be people taking risks for drug trafficking, and some will continue taking the drug," the council's executive director, David Ng, said on the same programme.

"After all, space oil has been popular among young people for over two years in Hong Kong. Right now, we can say the drug has taken root here. Information on how to buy and consume it is all over many circles among youngsters."

Ng called for different levels of intervention with young people, including new measures targeting those who smoke e-cigarettes, as these can be used to take the drug.