Within the first month of the recall, there was a 55% increase of people coming to Ontario-area emergency departments complaining of high blood pressure, said lead researcher Cynthia Jackevicius. She is a senior scientist with the Institute for Clinical Evaluative Sciences, in Toronto.
Some of these patients likely were valsartan users who stopped taking the blood pressure med after seeing scary recall news citing a potential carcinogen found in some lots of the drug, Jackevicius said.
“Nine out of 10 did have an alternative replacement” for valsartan within three months. “However, that means that one out of 10 did not,” Jackevicius said.
“That’s a little bit concerning, that some of these patients may have either been confused or concerned, and decided not to switch to another medication,” she added.
The recall occurred in July 2018 in both Canada and the United States, after generics maker Mylan Pharmaceuticals detected trace amounts of a probable cancer-causing chemical called N-nitrosodiethylamine (NDEA) in valsartan meds.
It was an unusually large recall that involved intense media interest, and Jackevicius and her colleagues wondered how it might have affected the drug’s users.
So they turned to Canadian prescription and medical records to track how valsartan users responded to the crisis.
Dr. Mary Norine Walsh, a past president of the American College of Cardiology and a cardiologist at St. Vincent Heart Center of Indiana, said, “It’s really interesting data, because my assumption would have been in Canada and the U.S. that substitution was made pretty much instantly.”
That’s what happened — mostly.
Within one month, 85% of patients had a new prescription for an alternative to their generic valsartan, Jackevicius said. By three months, 90% had a prescription for a different blood pressure drug.
But that left 10% of patients with recalled valsartan who hadn’t been prescribed an alternative, Jackevicius noted.
“Maybe they heard about the recall on the news and never went to their physician or clinician to get a substitution,” Walsh said.