The warning is based on data that suggest there is a higher frequency of non-fatal strokes, serious renal complications, hyperkalemia (high potassium levels in the blood) and hypotension (low blood pressure) in patients treated with aliskiren, the active compound in the drugs.
The advisory was issued in conjunction with Novartis Pharmaceuticals Canada Inc., which makes the drugs.
The concern stems from an interim review of data from the Altitude study, which was stopped early after the unexpected risks became apparent.
The adverse events were seen in people using the aliskiren-based drugs in combination with other blood pressure-lowering drugs known as angiotensin-converting enzyme (ACE) inhibitors or angiotensin receptor blockers (ARBs).
The statement says that people with Type 2 diabetes taking Rasilez or Rasilez HCT in combination with these other drugs should see their health-care provider and have their drug regimes altered as early as possible.
People should not stop their medications on their own, Health Canada said.