Editor’s Note: We’ve removed our paywall from this article so you can access vital coronavirus content. Find all our coverage here. To support our science journalism, become a subscriber.
The long list of potential COVID-19 treatments that researchers have suggested has one more addition: melatonin. A Texas doctor claims that he has treated 400 COVID-19 patients with the hormone, with few individuals developing severe enough cases to require hospitalization.
The announcement comes with no study to discern whether the supplement aided recovery or if this is just a coincidence, as a majority of COVID-10 cases don’t need hospitalization. The treatment appears to have provided vitamin C and vitamin D to patients as well. Neither vitamin qualifies as a verified and scientifically backed SARS-CoV-2 treatment, but their inclusion means that even if patient success was due to these supplements, the melatonin might not be the only factor.
Vague success claims aside, a handful of others have written about the possible ways melatonin might reduce the severity of a SARS-CoV-2 infection, and there’s currently a clinical trial running in the U.S. to examine this possibility. However, “at this time, early SARS-CoV-2 intervention with melatonin is not well supported,” says Cesar Borlongan, a neurologist at the University of South Florida. Much more rigorous research is needed to determine whether the molecule can do more than regulate sleep-wake cycles.
What Else Can A Sleep Aid Do?
Melatonin often goes by its nickname: the sleep hormone. Released by a gland in our brains, the molecule helps prepare our bodies for sleep — circulating levels of melatonin ramp up at night and drop off during the day. Melatonin supplements are often sold under the premise that the gummies or tablets will help people sleep. Research indicates the hormone could probably help with jet lag but there hasn’t been much evidence that melatonin could help with insomnia or other sleep conditions.
When it comes to COVID-19, those suggesting that melatonin might benefit infected individuals focus not on the way the molecules helps us sleep, but how it interacts with our immune systems. Research suggests that melatonin can help fight inflammation — or the reactions that spring up in our bodies when our immune systems detect a problem. A certain degree of inflammation is helpful for healing, but the response can also become excessive, like when our bodies target plaque on blood vessel walls.
In COVID-19 patients, some healthcare experts suspect that an overzealous immune response triggers health problems outside the lungs. For those interested in pursuing melatonin as a COVID-19 infection aid, this is where the molecule comes in, says Russel Reiter, who studies the aging process at the University of Texas Health Science Center at San Antonio. Reiter has written several articles about the potential melatonin might have, and he and colleagues in the Philippines published a paper where 10 hospitalized COVID-19 patients saw symptoms improve after a few days taking supplements.
Reiter has a lot of faith in melatonin, and if it is useful, the hormone would be a cheap treatment option compared with others in consideration for COVID-19. “There’s a large financial incentive to use melatonin,” Reiter says. So far, clinical trials investigating its use with COVID-19 patients are still running and have yet to reach a conclusion.
Melatonin On the Brain
Other researchers suggest that if melatonin is helpful during the pandemic, it might be for specific neurological issues. Compared with, say, the flu, SARS-CoV-2 might be more likely to cause strokes. And in pre-pandemic times, research found that sleep disorders might increase the risk for strokes as well as chronic inflammation. It’s possible to follow the logic and propose that if melatonin aids sleep or reduces inflammation, then the hormone could be helpful for preventing strokes — and maybe some COVID-19 patients could reduce their risk of brain damage if they take the supplement, says Borlongan. But so far, the research isn’t there to validate those conclusions. “It might be kind of a leap right now, to use melatonin early on,” Borlongan says.
If studies explore this connection, researchers would have to track whether or not COVID-19 patients given melatonin would develop strokes and look for evidence of its effect, Borlongan says. Does evidence for body-wide inflammation drop in patient blood samples? Then maybe the antioxidant is helping. Are the patients mostly just sleeping better? The perceived benefit could be due to rest, not melatonin specifically.
Like so many parts of the pandemic, there’s a lot of learning left to do about melatonin. Questions about its efficacy with the circulating coronavirus linger, along with how much someone would have to take for the hormone to make a difference. If this is a helpful COVID-19 aid, the good news is that researchers are looking into it, and we can wait and see what those studies conclude.
