New warnings of heart risks associated with the Type 2 diabetes drug Avandia are being added in Canada. (Paul Sakuma/Associated Press)

The diabetes drug Avandia now comes with warnings in Canada about heart risks, the drug's manufacturer said Thursday.

Canadians taking Avandia should make an appointment with their doctor as soon as possible about their treatment because of the Type 2 diabetes drug's potential risks, but not stop treatment abruptly, GlaxoSmithKline said.

The company, in consultation with Health Canada, announced new restrictions on the use of drugs containing rosiglitazone, such as Avandia, in people with Type 2 diabetes.

Package warnings say the drugs may increase the risk of serious heart problems, including heart failure, chest pain, heart attack and fluid retention.

The drugs should not be used in people who have or have had heart problems. People should talk to their doctor about other options before using the drug.

Based on Health Canada's review of recent data suggesting a higher risk of heart-related problems in patients treated with Avandia, the company has updated information for consumers and health-care professionals, including new restrictions on using the drug.

The restrictions include:

• Avandia, Avandamet and Avandaryl, brand names for rosiglitazone, are now indicated only in patients with Type 2 diabetes when all other oral medicines have not lowered blood sugar enough or are not appropriate.
• Patients currently taking the drugs should make an appointment with their doctor as soon as possible to discuss their diabetes treatment.
• Patients should not abruptly stop treatment based on these new restrictions, since stopping medications can cause poorer diabetes control with high blood-sugar levels.

Patients should discuss treatment options and the benefits and risks of rosiglitazone with their doctor and then complete an informed consent form.

Before filling in the form, doctors will ask patients to read the consumer information for the product, read and sign the form to show they understand the heart-related risks of the medication.

In September, the drug was taken off shelves in Europe while U.S. regulators restricted its use because of heart attack risks. At the time, the company said Health Canada was reviewing the proposed warning changes that are now in effect.

Avandia is used to treat Type 2 diabetes, the most common form of the disease, which is linked to obesity and afflicts 200 million people worldwide. This form of diabetes occurs when the body does not make enough insulin or cannot effectively use what it manages to produce.

Avandia helps sensitize the body to insulin.