The Canadian government announced today it is closing "loopholes" in a special access program that provides heroin to certain addicts.

At a news conference in Toronto Thursday, Health Minister Rona Ambrose said new regulations would also ban access to products containing unauthorized forms of cocaine and other restricted drugs, such as ecstasy and LSD.

Ambrose said those drugs won't be authorized for patients under new regulations that take effect immediately. She also said the ban won't affect clinical trials or university research.

The move comes a few weeks after Ambrose slammed her own department's decision to allow addicts to use the drug.

The special access program is designed to let patients in exceptional cases get medications normally not allowed in Canada.

She has said the decision violates the intent of the program and clashes with the government's anti-drug policy.

Asked about physicians who may strongly believe their patients need access to heroin, Ambrose replied they were free to make their case at their own provincial colleges of physicians and surgeons. But, she said, the federal government would no longer allow heroin to be prescribed through its special access program.

Ambrose also said the patients given access to heroin before the new regulations came into effect Thursday may continue their prescriptions for three months.

"Our goal must be to take heroin out to the hands of addicts," she said, adding that Prime Minister Stephen Harper agrees with her.

The Harper government has also strongly opposed the Insite supervised injection site in Vancouver, but lost a long legal fight to close it.

The Conservatives are using the heroin issue as a fundraising platform, saying the NDP and Liberals would make the program permanent if elected in 2015.