The government has moved to restrict prescribing of hydroxychloroquine to specialists after the US president described the drug as one of the “biggest game changers in the history of medicine” in a tweet based on preliminary results from a small French trial in 26 patients with COVID-19.

The TGA says prescribing is now restricted to physicians and specialists in dermatology, intensive care medicine, paediatrics and emergency medicine. GPs and other medical practitioners (e.g. hospital Resident Medical Officers (RMOs) and doctors in training) can continue to prescribe repeats for hydroxychloroquine to patients in line with the registered indications for patients in whom the medication was prescribed prior to 24 March 2020.

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

The open-label non-randomised clinical trial that triggered the US president’s claims appeared to show that hydroxychloroquine reduced viral load when combined azithromycin.

Other studies have suggested that hydroxychloroquine may inhibit attachment of the COVID-19 virus to the cell ACE2 receptor, and have inflammatory effects.

Donald Trump’s tweet wrongly suggested the drug would be fast tracked for approval by the FDA, a claim that was contradicted by government medical adviser Dr Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases. Dr Fauci said there was not yet any good evidence to support the effectiveness of hydroxychloroquine against COVID-19 and it would be premature to use it before it went through clinical trials.

But the presidential hyping of the drug has caused alarm among rheumatologists who fear limited stocks of hydroxychloroquine being diverted from patients using the drug for conditions such as lupus.

“We already have patients who need this drug for other diseases who are having trouble getting this drug because someone has persuaded doctors to give it to them – that’s in Australia and around the world,” Professor Eric Morand, head of rheumatology at Monash Health, told The Age.

The Pharmaceutical Society of Australia has called on to the government for a ban on dispensing of the drug except to those in whom it is clinically indicated.

“PSA is receiving reports from Australian pharmacists that they are receiving prescriptions from: doctors prescribing for other doctors and their families; as well as dentists prescribing to the community and their families; Non-medical prescribers prescribing bulk amounts of the drug,” it said in a letter to members.

“Our strong advice to pharmacists at this point in time, until further advice is available, is to refuse the dispensing of hydroxychloroquine if there is not a genuine need, and that need is for those indications for what it is approved for – inflammatory conditions or the suppression and treatment of malaria

In Australia, hydroxychloroquine is marketed as Plaquenil by sanofi-aventis, and there were 167,000 prescriptions dispensed via the PBS in 2018/19.

A clinical trial of hydroxychloroquine is about to start involving 60 hospitals across Australia to determine the best way to use the drugs in COVID-19. Led by Professor David Paterson, Consultant Infectious Diseases Physician at the Royal Brisbane and Women’s Hospital (RBWH) the trial will involve the use of hydroxychloroquine in combination with HIV antivirals.

Meanwhile billionaire Clive Palmer has pledged to pay for more than a million courses of the drug and said he had appointed Brisbane pharmacist Jeremy Sheridan to “lead the effort to oversee the large-scale manufacturing of the drug in Australia”.

Dr Paul Sufka, a rheumatologist in in St Paul, Minnesota said the early data for hydroxychloroquine appeared promising but further trials results are awaited.

“One thing that will have to be considered is that there could be a hydroxychloroquine shortage, so knowing who to treat, for how long, and how much will be important,” he said.