An Arizona man has died and his wife is in intensive care after attempting to self-medicate with chloroquine phosphate in an effort to protect themselves from the novel coronavirus, NBC News reported on Monday.

The woman who survived told NBC News that the couple got the idea to take chloroquine phosphate—also known simply as chloroquine—from President Donald Trump’s televised coronavirus task force briefings, in which he has touted the potential benefits of the drug in the fight against the coronavirus. Although epidemiologist and coronavirus task force member Anthony Fauci clarified to journalists that the evidence for chloroquine’s efficacy was “anecdotal,” Trump’s endorsement has already caused serious problems. Since he mentioned the drug, there has been a run on pharmaceutical supplies and two overdoses in Nigeria. Chloroquine phosphate is also used as a treatment for fish, and the Arizona couple had it on hand because they once had koi.

“I saw it sitting on the back shelf and thought, ‘Hey, isn’t that the stuff they’re talking about on TV?’ ” the Arizona woman told Vaughn Hillyard of NBC News. She and her husband then took a small amount of chloroquine phosphate mixed with soda, in hopes it would prevent them from being infected with the coronavirus. But the aquarium version of chloroquine phosphate is not the same formulation as the prescription drug: The couple both fell severely ill within 20 minutes, and the husband died on the way to the emergency room. Hillyard has posted audio of his interview with the survivor:

NBC: Did you see the President's press conference? Where did you hear about--



Patient: Yeah. Yeah, we saw his press conference. It was on a lot, actually.



NBC: And then did you did you seek out Chloroquine?



Patient: I had it in the house because I used to have koi fish. https://t.co/C8EiTQQ3r1 pic.twitter.com/QgmElANCEG — Vaughn Hillyard (@VaughnHillyard) March 24, 2020

The Food and Drug Administration has approved “compassionate use” trials of the drug in some cases to treat COVID-19, the disease caused by the novel coronavirus, but the drug’s actual effectiveness is unclear, as are the potential side effects for coronavirus patients. French researchers published promising results from an early clinical trial on March 20, but it involved only 20 patients. During his coronavirus task force briefing on Thursday, Trump billed the use of chloroquine to treat COVID-19 essentially as a risk-free miracle cure. “The nice part is, it’s been around for a long time, so we know that if it—if things don’t go as planned, it’s not going to kill anybody,” said the president.

On Sunday, Trump tweeted that hydroxychloroquine and azithromycin “have a real chance to be one of the biggest game changers in the history of medicine” and urged that they “be put in use IMMEDIATELY.”

And on Tuesday, the president tweeted a link to a New York Post story about a Floridian who believes that hydroxychloroquine saved his life:

A great early result from a drug that will start tomorrow in New York and other places! #COVIDー19 https://t.co/4F4Qk4WFtK — Donald J. Trump (@realDonaldTrump) March 23, 2020

Asked if she had a message for the American people, the Arizona woman was blunt. “Don’t believe anything the president says,” she warned. “And his people. Because they don’t know what they’re talking about.”

For more on the impact of the coronavirus, listen to Tuesday’s episode of What Next.