When Aimee Blou heard the lupus drug she has relied on for more than a decade promoted as a coronavirus antidote, she visited her pharmacist.

The 40-year-old woman from Stockton, California, was told the decades-old antimalarial drug commonly prescribed for lupus and rheumatoid arthritis was in short supply. She would get only a 30-day refill, not her typical 90-day supply.

“It’s all backordered,” the pharmacist explained to Blou on March 23. “We are not going to be able to give you these (90-day) refills."

Hydroxychloroquine, also sold under the brand name Plaquenil, has been touted by President Donald Trump, media personality Mehmet Oz and others as a COVID-19 treatment, though scientific evidence the drug is effective against the virus is lacking.

The renewed interest in chloroquine, an antimalarial drug available since 1944, and the similar drug hydroxychloroquine has made it difficult for pharmacies and hospital chains to manage a limited supplies, leaving patients like Blou fearful the shortage will harm their health.

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Blou usually takes two 200-mg pills of the drug each day to manage her lupus, an autoimmune disease that causes joint pain, stiffness, swelling, fatigue and organ damage. Hydroxychloroquine is the only medication that effectively reduces flareups, she said.

Because she was unable to fill her normal prescription, she is rationing her pills, taking a half-pillevery day – a quarter of her normal dosage. As of Friday, she had 39 pills left.

She has noticed everyday chores have become difficult. She struggles to get dressed, grip doors and start her car. Anything requiring her to make a fist or grip is too painful.

“When I have that medicine, I can live life normally and don’t have to think about it,” said Blou, who also has rheumatoid arthritis. “Now I have to stop and think before I even pick up my toothbrush to brush my teeth.”

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Prospect of not getting drug 'terrifying'

New York City resident and lupus patient advocate Peter Morley typically gets 90-day refills, but during a pharmacy trip on March 26, he too received a 30-day refill and no assurances he’d get another one. He returned again last week but was told he could not get an early refill.

His pharmacy, Walgreens, sent an email and explained the need to supply medication to COVID-19 patients. New patients would get a two-week supply of hydroxychloroquine. Existing patients such as Morley would be limited to 30 days as long as supplies are available.

Morley's doctor's office sent a message to him and other patients about potential changes in their prescriptions, including a lower dose or replacement drug to prevent flare ups. Patients can miss doses for several weeks without a disease flare, according to the message.

Morley, who takes other prescription drugs to control the disease, said hydroxychloroquine is the "one medication I can't live without."

He has had side effects such as nausea, vomiting, headaches and loss of appetite, but he has controlled those by adjusting his doses. The prospect of no longer getting the drug, he said, is "terrifying."

“I can end up in the hospital – the last place I need to be, especially someone who is immunocompromised," he said.

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A half-dozen manufacturers that make generic forms of the drug have reported limited availability of versions of the medication, according to the Food and Drug Administration's drug shortage list. For example, Teva Pharmaceuticals, an Israel-based generic drugmaker, had "limited supply, subject to allocation" for two versions of the drug – 200 mg pills in 500-count and 100-count bottles.

The Lupus Foundation of America has called on drug manufacturers to increase production of chloroquine and hydroxychloroquine, noting the efficacy and safety of these drugs for lupus are well known and routinely prescribed.

Large health providers such as Kaiser Permanente have changed how they prescribe the drug, citing a global shortage after it was identified as a possible treatment for COVID-19. Kaiser has limited refills for lupus patients up to 14 days and encouraged doctors to consider other drugs for patients, according to a Kaiser statement.

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'Suffering unintended consequences'

There are no proven treatments for those suffering from COVID-19, the disease caused by the new virus SARS-CoV-2, beyond supportive care that generally includes IV liquids, oxygen, fever reducers and painkillers.

Trump began touting chloroquine and hydroxychloroquine as promising treatments for COVID-19 during briefings in March and he has continued to mention the drugs on Twitter and his daily briefings.

The president and his supporters have cited small studies in France and China as evidence the federal government should aggressively pursue the antimalarial drugs as possible treatments.

But three small studies have reported less favorable results. A chloroquine study in Brazil was ended after six days when researchers found one-quarter of the patients taking the anti-malaria medication developed potentially deadly changes in the electrical system regulating their heartbeats.

A Centre for Evidence-Based Medicine analysis published this week counted 142 clinical trials registered to study chloroquine and hydroxychloroquine as treatments for COVID-19. The analysis concluded results from larger studies are needed and data from five smaller studies do not "support the use of hydroxychloroquine for prophylaxis or treatment of COVID-19."

Still, the federal government has pushed to make the medications available for COVID-19 patients. The Food and Drug Administration authorized emergency use of the drugs from the Strategic National Stockpile for hospitalized patients not part of a clinical trial.

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The Centers for Disease Control and Prevention published doses of chloroquine and hydroxychloroquine for COVID-19 patients, before removing the reference from its website, according to a New England Journal of Medicine article co-written by Dr. Benjamin Rome, an internist and health policy researcher at Brigham and Women’s Hospital and Harvard Medical School.

Rome said COVID-19 patients who receive higher doses of the drug are potentially being exposed to risks with no evidence the drug might benefit them. The impact on lupus and rheumatoid arthritis patients is a further risk.

“Because the drug has been widely promoted by the president, and indirectly by the FDA, there are shortages so patients who need the drug are having trouble getting it," Rome said.

While the antimalarial drugs have received widespread news coverage and dominated political discourse, several other antiviral medications and potential vaccines are being developed and studied. On Friday, investors bid up shares of Gilead Sciences on news the company's antiviral drug remdesivir showed promising results in patients at a Chicago hospital.

Seth Ginsberg is president and co-founder of the Global Healthy Living Foundation and CreakyJoints, a patient-advocacy group. He said his organization has heard from dozens of patients who can't get hydroxychloroquine or Plaquenil prescriptions filled because "this medicine is being excessively prescribed without evidence."

If studies show the drugs are an effective treatment for COVID-19, "that is the best case scenario," Ginsberg said. "Until then, we are suffering unintended consequences and jeopardizing our well being."

Congtributing: Elizabeth Weise