Doctors in Canada can now prescribe heroin to patients with particularly serious addictions to the drug, thanks to new rules that were recently approved by the country's government.

The rules, which went into effect last week, allow any doctor in Canada to apply to the country's national health department (known as Health Canada) for access to medical-grade heroin to prescribe to specific patients. The requests are approved on a case-by-case basis, by the government-run Special Access Programme, according to the new regulations.

However, the drug, known medically as diacetylmorphine, can be prescribed only to patients with severe heroin addictions who have tried to end their addiction multiple times with other methods but have failed, the government said.

"Having access to diacetylmorphine will provide health practitioners with an additional treatment option to treat patients with opioid dependence who have not responded to traditional treatments," the new regulations said. (Heroin belongs to the class of pain-relieving drugs known as opioids.) "Treatment with diacetylmorphine in a comprehensive setting can lead to improved treatment outcomes and health benefits for these patients." [10 Interesting Facts About Heroin]

The changes come at a time when opioid overdose deaths in Canada are on the rise. Not all provinces keep track of opioid deaths, but in British Columbia, there were 433 drug overdose deaths between January and July this year, a 75 percent increase over the number of deaths that occurred during that same period in 2015, according to a report from British Columbia Coroners Service. About 62 percent of all drug overdose deaths involved the opioid fentanyl, up from 30 percent of deaths in 2015.

A number of studies have shown that treatment with diacetylmorphine can help addicted patients who've previously failed other treatments. For example, a 2009 study in Canada found that patients with severe heroin addictions were more likely to stick with their addiction treatment and less likely to use illegal drugs if they received diacetylmorphine, compared to standard treatment with the drug methadone.

Prescriptions for diacetylmorphine are also available in some European countries, including Switzerland, Germany, the Netherlands and Denmark, to treat people with opioid dependence who have failed other therapies, the new regulations said.

Patients who get prescriptions for heroin will be supervised by medical staff when they are injecting the drug, according to CNN.

Original article on Live Science.