TORONTO -- Ontario's Liberal government is considering backtracking on medical marijuana exemptions to e-cigarette rules that are so new they haven't even technically come into effect.

The turnaround came just one day after the exemption for medical marijuana users to a vaporizing law came to light.

The government quietly exempted them this week from a law that bans the use of e-cigarettes anywhere regular cigarettes are prohibited. It means medical marijuana users can vaporize in restaurants, at work or on playgrounds under the regulations that are set to come into effect Jan. 1.

Associate Health Minister Dipika Damerla said based on feedback such as media reports and online comments, the government will take another look at the exemption.

"I think until we take a good look at what the feedback is and what the best way forward is, it's too early to say whether this was a failure or not," she said.

"But I think it's really important for governments to be responsive and we've heard some feedback over the last 24 hours and we're committing to take a look at that feedback."

Damerla wouldn't say if the second look at the exemptions would be completed before Jan. 1.

She said Wednesday that employers or restaurant owners could still ban medical marijuana users from vaporizing on the premises.

Damerla said the exemptions were drafted with the advice of legal counsel, but wouldn't say what considerations were made about an onus put on business owners to ensure anyone vaporizing marijuana had a legitimate prescription.

"We have heard from medical marijuana patient advocacy groups that users of medical marijuana may need to vaporize marijuana in emergency circumstances if they sense a seizure or other symptom of their illness about to occur," she said in a statement.

"The intention of this regulation was to balance users of medical marijuana with establishment owners."

The legal advice was that there is no scientific evidence that second-hand marijuana vapour produced from an electronic cigarette has any health effects on bystanders, Damerla said. Not providing an exemption for medical marijuana users could raise constitutional issues, she said she was told. Jonathan Zaid, the founder of Canadians for Fair Access to Medical Marijuana, has said medical cannabis users tend to be discreet, so most likely won't be lighting up in a public area.

The regulations define a vaporizer as an electronic cigarette or other device that contains a power source and heating element that's designed to heat a substance to produce a vapour to be inhaled through the mouth.

Progressive Conservative Leader Patrick Brown said it sounds like the government needs to do more homework.

"We do want to accommodate medical needs that exist in Ontario," he said. "I'm going to be hopeful the government will get this right and make sure it's consistent with municipalities and their bylaws."

Deputy NDP leader Jagmeet Singh said it shows the Liberal government is not doing its job properly.

"This is another example of leading first with a policy then afterwards realizing, 'Wait, we didn't consult properly and people are now upset,"' he said. "Surprise."