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An Arizona man has died and his wife was in critical condition after consuming chloroquine phosphate, a product used to clean fish tanks that shares an active ingredient with drugs touted by President Donald Trump as a possible treatment for the novel coronavirus, COVID-19.

The man’s wife, who has not been named publicly, told NBC News that she and her husband decided to ingest the aquarium product after hearing Trump on TV refer to two anti-malaria drugs — chloroquine and hydroxychloroquine — as a potential “game-changer” in the fight against COVID-19.

“I saw it sitting on the back shelf and thought, ‘hey, isn’t that the stuff they’re talking about on TV?’” the woman told NBC. 

The couple, both in their 60s, had not been diagnosed with COVID-19, but the woman said they were worried about contracting the disease and had taken the aquarium product as a preventative measure. 

The product they consumed contained the same active ingredient as the two anti-malaria drugs Trump referred to — but unlike the medicine taken by humans, the product they ingested is used to get rid of algae and a parasite that causes a condition known as white spot disease in fish. According to The New York Times, prices for the aquarium product “have spiked during the coronavirus pandemic.” 

Banner Health, a hospital system based in Phoenix, Arizona, said the couple experienced distressing side effects within 30 minutes of consuming the product and were admitted to one of their hospitals.

“I started vomiting,” the woman told NBC News. “My husband started developing respiratory problems and wanted to hold my hand.”

The man died shortly after arriving at the hospital from cardiac arrest. His wife was initially under critical care, but the Times said her condition has since stabilised and she’s expected to make a full recovery. 

Banner Health issued a strong warning to the public to not ingest “inappropriate medications and household products,” including chloroquine, “to prevent or treat COVID-19.” 

Federal officials have said they are looking into the safety and efficacy of chloroquine and hydroxychloroquine in treating COVID-19. In the meantime, however, medical experts have warned of the drugs’ dangerous side effects and stress that only anecdotal evidence exists so far of their potential to treat the new coronavirus.

“Given the uncertainty around COVID-19, we understand that people are trying to find new ways to prevent or treat this virus, but self-medicating is not the way to do so,” Dr Daniel Brooks, medical director of Banner Health’s Poison and Drug Information Center, said in a statement. “The last thing that we want right now is to inundate our emergency departments with patients who believe they found a vague and risky solution that could potentially jeopardise their health.” 

It’s never a good idea for humans to consume aquarium products as medicine.

The Smithsonian magazine warned the public in 2017 against taking fish antibiotics to treat their own illnesses after noting the practice was a trend that stretched back at least to the 1990s. 

The Arizona widow urged people this week to learn from her and her husband’s mistake. 

“Be careful and call your doctor,” she said. “This is a heartache I’ll never get over.”