An Arizona man had died after taking chloroquine in an attempt to prevent coronavirus infection. The man’s wife also took the drug and is currently under critical care.

It was found that the toxic drug that ingested was not the actual form of chloroquine that is used for treating malaria in humans. Rather, it was a chemical used in a parasite treatment for fish.

Although no drugs have been approved for the treatment of COVID-19, some early studies have shown that chloroquine could be effective.

Speaking to NBC News, the man’s wife said she had watched TV briefings in which President Donald Trump optimistically talked about the “very encouraging results” of chloroquine in treating coronavirus.

Something clicked her mind when she heard the word “chloroquine,” She had used the ingredient to treat her koi fish. The woman said, “”I saw it sitting on the back shelf and thought, ‘Hey, isn’t that the stuff they’re talking about on TV?’”

The couple, both in their 60s, decided to mix the ingredient with a liquid and drink in an attempt to prevent the virus. The man’s wife said, “We were afraid of getting sick.”

They became extremely ill with 20 minutes and started felling “dizzy and hot.” The woman said, “I started vomiting. My husband started developing respiratory problems and wanted to hold my hand.”

She called 911. The emergency responders asked her what they had consumed. She said, “I was having a hard time talking, falling down.” He husband died shortly after arriving at the hospital.

Medical Director of Banner Poison and Drug Information Center Dr. Daniel Brooks said in a statement, “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.”

The Nigeria Centre for Disease Control (NCDC) tweeted, “#FactsNotFear@WHO has NOT approved the use of chloroquine for #COVID19 management. Scientists are working hard to confirm the safety of several drugs for this disease.”

“Please DO NOT engage in self-medication,” it added. “This will cause harm and can lead to death.#COVID19Nigeria.”

The U.S. Food and Drug Administration (FDA) has not approved chloroquine or hydroxychloroquine for the treatment of the coronavirus.

The man’s wife has warned other to listen to doctors for the best advice on coronavirus prevention. She said, “Be careful and call your doctor. This is a heartache I’ll never get over.”