O'FALLON, Ill — When Valarie Mueth refilled her prescription for hydroxychloroquine three weeks ago, she didn't realize requests for the rheumatoid arthritis drug were about to spike.

"The more I heard about it, the more concern I have because it’s a drug that I need," Mueth said. "I am very concerned about availability; I'm especially concerned about the price."

At this time, there is no proven cure or treatment for coronavirus, but hydroxychloroquine has been touted as a possible remedy, causing demand to rise.

Mueth has paid as much as $200 per refill for hydroxychloroquine — the generic version of Plaquenil — but her current out-of-pocket price is closer to $50. 

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The autoimmune disorder has already affected two of Mueth's fingers and she said any disruption in her supply would be serious.

"I would be in severe pain every day," Mueth said. "I would have a lot of swelling in my joints, especially my knees and my feet. And my hands would begin to cripple."

As demand rises, she worries stockpiles will plummet. And her pharmacist said those concerns are well-founded.

"Most of us don't stock large amounts of anything in our pharmacy," pharmacist Jackie Howell said. "If it goes outdated, it's not any good."

Owner of The Medicine Shoppe in O'Fallon, Illinois, Howell has two customers who rely on the drug, one of whom reports that they can't get out of bed without it. So, Howell's keeping an eye on her reserves, and she called four suppliers with no luck.

"Right now, they're out of it," Howell said. "The ones that do stock it are showing a limited supply, so you can only order so many pieces per day. We have had some instances where some doctors in the area are calling in for their spouses, so that they can have it on hand in case they get [COVID-19]."

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With an increasing demand for the product, state regulators with the Missouri Board of Pharmacy and Missouri State Board of Registration for the Health Arts filed a joint statement with guidelines for prescribers and pharmacists.

The letter states that doctors should not write prescriptions for preventative use against the coronavirus, and instructs pharmacists "should use their professional judgment" in whether or not they fill prescriptions for new patients.

You can read the full statement below.

Medical experts also question the effectiveness of the drug against COVID-19 which is frustrating for people like Mueth who rely on its anti-inflammatory properties.

"I wish they would just stop and wait until medical science has proven that is the answer," Mueth said.

It's unclear if that answer will come before Mueth's 90-day refill runs out.

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