Off-label prescribing of an antipsychotic drug in Canada is raising concerns about serious and life-threatening side effects.
Seroquel is only approved in Canada to treat bipolar disorder and schizophrenia. In the United States, however, it is also used as an add-on treatment to an antidepressant for patients with major depressive disorder.
According to IMS Health Canada, a company that tracks the health care industry, the number of prescriptions for Seroquel in Canada has risen from 4.1 million in 2008 to 7.4 million in 2013. However, the prescriptions for the drug are vastly disproportionate to the number of Canadians suffering from schizophrenia and bipolar disorder, suggesting that the drug is being prescribed for conditions for which it is not approved.
“Often what we see is people taking this drug primarily as a sleep aid, and that’s very bad medicine and I think that it’s something that should be discouraged,” says Dr. David Juurlink, head of the division of clinical pharmacology and toxicology at Sunnybrook Health Sciences Centre in Toronto.
In the U.S., doctors have the authority to prescribe drugs for conditions for which they are not approved. However, drug companies by law cannot market drugs for unapproved uses. In Canada, the rules are a bit foggy. Off-label prescribing is not regulated by any one agency thus there is no true accountability.
Where this becomes a problem is in side effects. Seroquel side effects include diabetes, hyperglycemia, and complications from blood clots. It is similar to the antipsychotic Risperdal, also known as risperidone, and carries the same risk for gynecomastia, a condition in which boys and men develop breasts. Treatment often requires surgeries such as liposuction or mastectomy.
Off label prescribing of antipsychotics is concern and doctors and patients should use caution, Juurlink says. “This is a drug that can kill people, period. And it’s difficult sometimes to know who those people are going to be.”