That's more money than Health Canada spent advertising all its programs and services combined in the previous 2013-14 fiscal year.
A government response to a House of Commons order paper question by Liberal MP Scott Simms said the ad campaign to raise awareness of the harms of marijuana and prescription drug abuse among youth cost $7,026,822.
The campaign's target audience was parents, the government response said.
The taxpayer-funded TV and Internet ads by Health Canada ran parallel to a partisan radio ad campaign, paid for by the Conservative party, that attacked Liberal Leader Justin Trudeau over his promise to legalize, regulate and tax marijuana.
"Governments have been communicating the dangers of drugs for decades and will continue to support parents with the tools they need to ensure children live drug-free lives," Michael Bolkenius, a spokesman for Health Minister Rona Ambrose, said in an email Tuesday.
"By contrast, Justin Trudeau's Liberal plan to legalize marijuana will make smoking marijuana a normal, everyday activity for Canadians. We do not support making access to illegal drugs easier. Legalizing marijuana would make it easier for kids to buy and smoke."
Ralph Goodale, the Liberal deputy leader, said in an interview that the coincidental public and party ad campaigns call into question the government's motives.
But he said the ads themselves failed to relay the most important public message: That Canadian youth are the biggest pot consumers in the western world, according to the United Nations.
That is evidence the long-standing drug prohibition policy is a failure, said Goodale.
"There obviously need to be changes and the government has just spent $7 million propping up the status quo, which doesn't work," said Goodale.
The money spent on the government's anti-pot ads dwarfed the $5.2 million Health Canada spent advertising in the previous year on a host of issues, including food safety, immunization, adverse drug reactions and the health and safety of Canadians.
Documents released Tuesday show the health minister hosted two roundtables with drug policy stakeholders last year, one in January and one in April, in advance of the anti-drug campaign.
Despite the consultation, three national medical organizations ended up very publicly distancing themselves from the project.
The Canadian Medical Association, the College of Family Physicians of Canada and the Royal College of Physicians and Surgeons of Canada issued a release last August saying they would not endorse the government ads.
"The educational campaign has now become a political football on Canada's marijuana policy," said their joint statement.
"We did not, and do not, support or endorse any political messaging or political advertising on this issue."
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