Should we be studying melatonin for the prevention or treatment of COVID-19? I say yes and so does Dr. Harold Pupko, a North Toronto general practitioner/psychotherapist.

Dr. Pupko is president of the North York Branson Medical Society (with over 500 Toronto area physicians). He recently sent a recording of the organization’s AGM scientific session on the subject. I found it intriguing.

The mechanism of action of melatonin on COVID-19 is unknown, but what is known is that it counters the oxidative stress generated by the viral infection, and helps convert type 1 macrophages, which are pro-inflammatory, to type 2 macrophages, which are anti-inflammatory. Melatonin is not viricidal but may interfere with replication.

I interviewed Dr. Pupko and Dr. Greg Brown, a retired Toronto psychiatrist still very actively involved in melatonin research, as he has been his entire professional life. I also spoke with Dr. Richard Neel, a family doctor in Texas. They are all proponents of melatonin and the latter two are taking it themselves to avoid COVID-19. The dose is 12.5 mg daily. Dr. Neel is prescribing it to patients with COVID-19. He is seeing up to 20 COVID patients per day.

Dr. John Crosby

Melatonin was one of several medications President Donald Trump was given at Walter Reed Hospital when he was being treated for COVID-19 last fall.

There have been no large double-blind crossover prospective trials, but the Cleveland Clinic did a review of patient charts and found a 30% reduction in the likelihood of testing positive.

At the New York-Presbyterian/Columbia University Irving Medical Center, an analysis of intubated patients treated with melatonin showed a significant association with survival.

Very recently, a randomized controlled trial from the Baqiyatallah University of Medical Sciences in Tehran provided a preliminary report that hospitalized COVID-19 patients (24 vs. 20 controls) showed significantly reduced symptoms and earlier discharges when treated with melatonin 3 mg, three times daily.

These are small numbers (but) melatonin is a natural hormone that is very cheap and harmless at low doses for most people. Its main side effect is sleepiness so you can take it before bedtime. It has few interactions with other drugs but can cause more disturbing side effects in some people, especially at high doses.

Learn more about the ongoing Cleveland Clinic research on melatonin here.

Dr. John Crosby is a family physician in Cambridge, Ont. This article was originally published in The Medical Post. 

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