One of the drugs President Trump has touted as a potential "game changer" to treat COVID-19 is a vital medication for patients with lupus. However, the drug — hydroxychloroquine — has not been clinically tested or approved to treat coronavirus, and the nation's top infectious disease expert says there is no evidence it is effective.

Now there are reports of people stockpiling the drug, and people with lupus say they are struggling to fill their long-standing prescriptions.

HYDROXYCHLOROQUINE & AZITHROMYCIN, taken together, have a real chance to be one of the biggest game changers in the history of medicine. The FDA has moved mountains - Thank You! Hopefully they will BOTH (H works better with A, International Journal of Antimicrobial Agents)..... — Donald J. Trump (@realDonaldTrump) March 21, 2020

Dr. Anthony Fauci, the director at the National Institute of Allergy and Infectious Diseases at NIH, called Mr. Trump's assertions about hydroxychloroquine "anecdotal" and said there is no evidence that it is effective for COVID-19 patients. But that apparently has not stopped people for seeking out the drug. The Lupus Foundation of America released a statement warning "these drugs may be in high demand in the coming weeks."

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"We are actively working with our medical and scientific advisors, other patient groups, partners, and the federal government to take steps that ensure people with lupus will be protected from a disruption in access to critical medications," the foundation said, adding that "hospitals and clinics that treat people with lupus also are working to ensure that those with existing prescriptions will be able to continue their course of treatment."

The foundation noted that researchers in China and France have tried hydroxychloroquine and chloroquine, which are also anti-malarial drugs, as treatments for pneumonia caused by the coronavirus. The World Health Organization has launched a global clinical trial to study the potential effectiveness of a number of drugs to treat coronavirus, including hydroxychloroquine and chloroquine.

But Science magazine reports, "In guidance published on Friday, the US Society of Critical Care Medicine said that 'there is insufficient evidence to issue a recommendation on the use of chloroquine or hydroxychloroquine in critically ill adults with COVID-19.'" It adds that hydroxychloroquine, in particular, can have side effects, in some cases affecting the heart, which could be a serious concern for vulnerable COVID-19 patients.

Lupus, also known as Systemic Lupus Erythematosus (SLE), is a chronic autoimmune disease that can affect the joints and almost every major organ in the body, including the heart, kidneys, skin, lungs and brain. As many as 1.5 million people in the United States have lupus.

On Sunday, ProPublica reported that people with the debilitating disease are already struggling to fill their prescriptions of hydroxychloroquine (also called Plaquenil). Medical professionals and people with lupus have taken to social media to call attention to the issue.

"Pharmacies are running out and insurance companies are requiring new prior authorizations," one doctor wrote. "The end result: #lupus and other rheum patients aren't getting the medications they need." A patient tweeted, "lupus patients like myself need help. Pharmacies are out of stock of plaquenil. I personally called dozens of pharmacies in NYC and had friends calling in Boston. This is endangering lives." Another patient wrote, "I need this drug to live."

Hi - lupus patients like myself need help. Pharmacies are out of stock of plaquenil. I personally called dozens of pharmacies in NYC and had friends calling in Boston. This is endangering lives. There must be something to ensure we can get this drug that we have to take daily. — cat (@schrodingercat) March 22, 2020

People are overprescribing hydroxychloroquine for #COVID19, and now pharmacies are running out and insurance companies are requiring new prior authorizations. The end result: #lupus and other rheum patients aren’t getting the medications they need. #medtwitter — Jack Turban MD (@jack_turban) March 23, 2020

I keep hearing from patients with lupus, rheumatoid arthritis and Sjogren's syndrome. This is real. Lupus Patients Can’t Get Crucial Medication After President Trump Pushes Unproven Coronavirus Treatment https://t.co/xUQ2zvv7KI — Charles Ornstein (@charlesornstein) March 22, 2020

I have SLE and my refill for for hydroxychloroquine was just denied. The pharmacy received direction that no refills of the drug are to be given at this time!?! They said they would contact my doctor to discuss alternatives?! There are no alternatives! I need this drug to live. — Dale (@proud_mom629) March 21, 2020

I've been off of it for awhile but my doctor wanted to put me back on it. No pharmacies in my area can get it now. I'm in a flare and need some type of help. Steroids are a no go for me because I'm diabetic. I have no clue what I'm going to do. #Lupus #COVIDー19 https://t.co/U7ghwwwdzW — SilverAcidRain (@SilverAcidRain) March 22, 2020

#Hydroxychloroquine is a life-saver for those of us with #lupus and other autoimmune conditions. Until actual scientists have been able to complete actual research on whether it works on coronavirus, please do not stockpile/hoard the medicine I need to function. — Janet Craswell (@JanetCraswell) March 22, 2020

Hi - lupus patients like myself need help. Pharmacies are out of stock of plaquenil. I personally called dozens of pharmacies in NYC and had friends calling in Boston. This is endangering lives. There must be something to ensure we can get this drug that we have to take daily. — cat (@schrodingercat) March 22, 2020

Authorities in Nigeria say hospitals there have seen cases of chloroquine poisoning after Mr. Trump touted the drug as a treatment against the new coronavirus.