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The Douglas County coroner is reporting a 74-year-old Colorado woman died of "ivermectin toxicity" in August, CBS News Colorado has learned. It's the second such death in the state, and it's triggering renewed cautions about the different forms of ivermectin.

"It's safe when used as prescribed," said Dr. Shireen Banerji, Director of the Rocky Mountain Poison Center.

"It's not safe when you are using veterinary medicine not prescribed for you -- it's not the right formulation," said Banerji.

According to a Douglas County Coroner's Office autopsy report, Mary Doran died on Aug. 2 after a series of seizures due to "probable ivermectin toxicity." The report describes her death as an accident. According to the report obtained by CBS News Colorado, Doran had reportedly been taking ivermectin "for chronic pain." It states: "The decedent and her husband were reportedly taking ivermectin intermittently over the past year which was being taken 2 times a day over the past 6 days. ... Ivermectin was present at the decedent's home."

The container of ivermectin found in Doran's home was a type of ivermectin for animals. The box warns the medication is "for oral use in horses only." The coroner's report notes Doran had no prior history of seizures and there was no other explanation for what might have caused Doran's seizures.

The report notes: "There is currently no available toxicology testing available for the confirmation of ivermectin."

The Colorado Department of Public Health and Environment said this was only the second death in the state since 2020 mentioning possible or probable ivermectin toxicity as the cause. The agency said it had no records of ivermectin deaths from 2010-2020.

According to an online obituary, Mary Doran had lived in Highlands Ranch for 30 years with her husband. She had been a respiratory therapist in four states.

Ivermectin to treat parasites in animals is widely available online and at farm and ranch stores. But it's far more potent than the type of ivermectin prescribed for humans. Human ivermectin is used to treat various parasitic illnesses and is considered safe.

"There's a monumental difference between veterinary-grade ivermectin and ivermectin for human consumption," Douglas County Coroner Raeann Brown told CBS News Colorado.

Brown said humans ingesting equine ivermectin can suffer "adverse side effects that could lead to death."

Ivermectin rose to prominence during the COVID-19 pandemic as it was promoted on social media as effective in preventing or treating COVID.

"That is not true," said Banerji. "There is no data that would say it's effective against COVID."

Without prescriptions for ivermectin for people, many Americans bought the easily accessible veterinary versions and took it. Banerji said the number of calls to the Poison Center about ivermectin doubled during COVID as many people got sick from ingesting the livestock version of the medication, which is much more concentrated as its formulated for large animals. Other poison control centers reported similar spikes in calls during COVID from users who had bought and used the veterinary version and fell ill. The National Poison Data System reported a 245% increase in ivermectin overdoses during COVID, as Americans sought COVID prevention and treatments.

Since the pandemic, at least four states have passed laws allowing human ivermectin to be sold over the counter, and nine other states are weighing similar legislation.

"We hope people really pay attention to the dangers of this. Everyone thinks they know better or this will never happen. It's happening more than people think," said Lisa Doran, Mary Doran's stepdaughter.

The Douglas County Sheriff's office said "we are conducting a death investigation" regarding Mary Doran's death, but spokesperson Deborah Takahara said "no further information is available at this time."

Ivermectin blamed for death of Colorado woman; experts renew warnings about misuse of drug