Health Canada has approved plans to create four new supervised consumption sites in British Columbia and Quebec, but some health officials say the approvals fall short of meeting the needs in communities devastated by overdose deaths.

A statement from Health Minister Jane Philpott on Friday said the approval of the sites is one step in combating the ongoing illicit opioid "overdose epidemic" gripping the country.

The sites allow people to use illicit drugs under the supervision of a medical professional in case they overdose.

But at a conference in Vancouver, health officials said restrictions mean only people who inject drugs can receive supervision, not those who use drugs in other forms.

"From a medical health and public health perspective, all modes of consumption can be dangerous and should be supervised, so it's incomprehensible to me that there would currently be this restriction," said Dr. Perry Kendall, B.C.'s chief provincial health officer.

Two of the new sites are in Surrey, B.C., one is in Vancouver and a mobile consumption site has been approved to operate in Montreal.

Vancouver Coastal Health chief medical health officer Dr. Patricia Daly said existing overdose prevention sites support people who ingest drugs in many forms, including orally.

"When we open our doors with the Health Canada exemption, it will be difficult to deny people the ability to consume drugs in the way that they're used to," she said.

"Ultimately, I think we have to realize our crisis here is not just among people who inject drugs."

Kendall said he suspects the restriction is due to a lack of published documentation on the effectiveness of supervised consumption for drugs that are ingested in ways other than by injection.

But he said there is enough evidence through the overdose prevention sites that have operated in B.C. since December to prove it saves lives.

"We've reversed hundreds of overdoses and there's never been a death," he said.

B.C. has been the epicentre of the overdose crisis, where over 1,200 people have died between the start of 2016 to the end of March this year. The provincial coroner said many of the deaths have been caused by fentanyl, a powerful opioid.

Provincial health officials did acknowledge that the approvals are a step in the right direction.

In a news release, Fraser Health chief medical health officer Dr. Victoria Lee said the exemption "will allow us to take a significant step forward in engaging with this population."

Quebec's Public Health Minister Lucie Charlebois also issued a statement welcoming the approval of the Montreal mobile site.

"This demonstrates that Quebec is a leader in preventative health care and drug-related harm reduction, and that we are setting an example for other communities that will follow suit in this area," her release said in French.

Health Canada said the mobile site in Montreal is the first of its kind to be approved in Canada, and will provide a "geographically flexible" service to clients.

The mobile site is supposed to provide additional services that compliment three fixed sites that were approved by Health Canada in February.

Canada's two existing supervised consumption sites are both located in Vancouver.

Health Canada said evidence shows supervised consumption sites save lives and decrease the transmission of disease without increasing drug use or crime in the surrounding area.