Health care workers in Ontario were advised Monday not to give patients a questionable combination of drugs that U.S. President Donald Trump and others on social media have claimed can treat patients suffering from the novel coronavirus (COVID-19).

In a joint message to members, the provincial associations for doctors, pharmacists and registered nurses said there is a lack of evidence to suggest hydroxychloroquine and azithromycin can treat COVID-19, noting prescriptions for the combination of the drugs in Canada have soared following the “exponential growth” in social media posts citing anecdotal reports of the drugs’ effectiveness.

As a result, Canada is now facing a shortage of hydroxychloroquine, which is intended for use as a treatment for rheumatoid arthritis, lupus and to prevent and treat some acute attacks of malaria, according to the statement from the Ontario Pharmacists Associations (OPA), Ontario Medical Association (OMA) and Registered Nurses Association of Ontario (RNAO). The groups warned that shortages of the drug present “very serious challenges for long-term continuity of care for patients” suffering from those illnesses.

“It is not at all surprising that patient demand for these products has been and will continue to be high, especially if demand goes unchecked,” the associations said in a statement, adding that health care providers have an obligation to educate patients about evidence-based treatments, “particularly for COVID-19.”

“At this time, there is a serious lack of evidence that categorically supports the widespread use of hydroxychloroquine and azithromycin.”

Against the advice of his top health officials, Trump over the past few days has encouraged use of the prescription drugs to treat COVID-19. In one tweet on Saturday, the president claimed that “taken together, (the drugs) have a real chance to be one of the biggest game changers in the history of medicine.”

(iPolitics is not linking to the tweet to discourage the sharing of inaccurate information.)

While there is still a sufficient stockpile of azithromycin available in Canada, the health care worker associations warned that over-prescribing the antibiotic could contribute to antimicrobial resistance. Azithromycin is used in the treatment of some mild to moderate infections including pharyngitis, tonsillitis, pneumonia and some lower respiratory tract infections.

“At this time, there is a serious lack of evidence that categorically supports the widespread use of hydroxychloroquine and azithromycin,” says the health care worker associations’ statement.

The full statement from the OPA, OMA and RNAO to its members on the use of hydroxychloroquine and azithromycin is here.

READ MORE: Ontario promised 50,000 more COVID-19 test kits by federal government

In a separate notice to sent just to doctors, the OMA said that “extremely preliminary results” have shown that combining the drugs “may” have shortened the amount of time the coronavirus remains in a patient, but that there’s no evidence that they’re effective in treating or preventing COVID-19.

“Do not prescribe these drugs pending further evidence-based recommendations,” the OMA told doctors on Monday.

OMA President Dr. Sohail Gandhi told iPolitics last week that he’s been repeatedly stressing that people need to be wary of unproven information about COVID-19.

“I stress to my patients and I stress to anyone who asks is that because information is evolving so quickly about this virus, there is a tremendous amount of fake and inappropriate information online about this virus, and that’s very difficult to deal with,” Gandhi said.

“As evidence-based clinicians, we must be diligent in our efforts not to let blind hope drive our decisions,” the OPA, OMA and RNAO’s group statement from Monday says.

READ MORE: How did we miss the COVID-19 outbreak and what are we missing now?

On Monday, Prime Minister Justin Trudeau announced that the federal government would invest $275 in efforts to find a cure for COVID-19, including $192 million in companies that include AbCellera and Medicago.

Technology produced by Vancouver-based AbCellera is being used to search blood samples of patients who have recovered from the illness in an attempt to pin-point naturally produced antibodies that can be used for treatment of the coronavirus.

Quebec City-based Medicago has identified a plant-based vaccine candidate for COVID-19, which is currently in the pre-clinical testing phase. A press release from the Prime Minister’s Office said funding will allow the company to more rapidly conduct clinical trials and eventually shift to and scale up production if it’s vaccine proves viable.

A $23 million chunk of the funding will be given to the University of Saskatchewan’s Vaccine and Infectious Disease Organization, to allow it to strengthen its research on COVID-19 and to help it develop a vaccine for the illness.

Another $15 million portion is being used by the National Research Council of Canada to upgrade its Montreal facilities to allow for the scaling-up of promising vaccine candidates for industrial production.

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