Melatonin is a hormone synthesized in your pineal gland and several other organs,1 indeed in most cells, including human lung monocytes and macrophages, as it is actually synthesized in your mitochondria.2
While most well-known as a natural sleep regulator, melatonin also has many other important functions.3 Notably, it plays an important role in cancer prevention4 and may prevent or improve certain autoimmune diseases, such as Type 1 diabetes.5
It also has anticonvulsant and antiexcitotoxic properties,6 and is a potent antioxidant7 with the rare ability to enter your mitochondria,8 where it helps prevent mitochondrial impairment, energy failure and the death of mitochondria damaged by oxidation.9 It also:
- Boosts immune function
- Helps recharge glutathione10 (and glutathione deficiency has been linked to COVID-19 severity)
- May improve the treatment of certain bacterial diseases, including tuberculosis11
- Helps regulate gene expression via a series of enzymes12
As noted in the Journal of Critical Care:13
“Melatonin is a versatile molecule ... Melatonin
plays an important physiologic role in sleep and circadian rhythm
regulation, immunoregulation, antioxidant and mitochondrial-protective
functions, reproductive control, and regulation of mood. Melatonin has
also been reported as effective in combating various bacterial and viral
infections.”
Melatonin Also Has Important Role in COVID-19 Treatment
Over the past two years, melatonin
has emerged as a surprise weapon against COVID-19. It’s been shown to
play a role in viral, bacterial and fungal infections14 and as early as June 2020, researchers suggested it might be an important adjunct to COVID-19 treatment.15,16,17 According to the authors of that paper, melatonin attenuates several pathological features of COVID-19, including:18
- Excessive oxidative stress and inflammation
- Exaggerated immune response resulting in a cytokine storm
- Acute lung injury
- Acute respiratory distress syndrome
In October 2020, a scientific review,19
“Melatonin Potentials Against Viral Infections Including COVID-19:
Current Evidence and New Findings,” summarized the mechanisms by which
melatonin can protect against and ameliorate viral infections such as
respiratory syncytial virus, viral hepatitis, viral myocarditis, Ebola,
West Nile virus and dengue virus.
Based on these collective findings, they hypothesized melatonin may
offer similar protection against SARS-CoV-2. One mechanistic basis for
this relates to melatonin’s effects on p21-activated kinases (PAKs), a
family of serine and threonine kinases. The authors explain:20
“In the last decade, PAKs have acquired great
attention in medicine due to their contribution to a diversity of
cellular functions. Among them, PAK1 is considered as a pathogenic
enzyme and its unusual activation could be responsible for a broad range
of pathologic conditions such as aging, inflammation, malaria, cancers
immunopathology, viral infections, etc ...
Interestingly, melatonin exerts a spectrum of
important anti-PAK1 properties ... It has been proposed that
coronaviruses could trigger CK2/RAS-PAK1-RAF-AP1 signaling pathway via binding to ACE2 receptor.
Although it is not scientifically confirmed as yet,
PAK1-inhibitors could theoretically exert as potential agents for the
management of a recent outbreak of COVID-19 infection. Indeed, Russel
Reiter, a leading pioneer in melatonin research, has recently emphasized
that melatonin may be incorporated into the treatment of COVID-19 as an
alternative or adjuvant.”
Melatonin Lowers COVID-19 Mortality
Then, on the last day of 2021, Melatonin Research published a research commentary21 discussing an October 2021 study22
by Hasan et. al., which found melatonin significantly lowered mortality
when given to severely infected COVID patients. According to the
authors:
“In a single-center, open-label, randomized clinical
trial, it was observed that melatonin treatment lowered the mortality
rate by 93% in severely-infected COVID-19 patients compared with the
control group.
This is seemingly the first report to show such a
huge mortality reduction in severe COVID-19 infected individuals with a
simple treatment. If this observation is confirmed by more rigorous
clinical trials, melatonin could become an important weapon to combat
this pandemic.”
The commentators point out that, at less than $5 per course of
treatment, melatonin is a cost-effective addition to any treatment plan.
For comparison, Regeneron monoclonal antibodies cost about $2,100 per
dose and remdesivir is $3,100 per treatment. Melatonin also has no
serious side effects, so it can be universally used.
The Hasan trial23 included 158 hospitalized COVID patients between the ages of 18 and 80. All had confirmed severe SARS-CoV-2 infection.
Eighty-two of the patients were enrolled in the melatonin arm and
received 10 milligrams (mg) of melatonin half an hour before bedtime for
14 days, in addition to standard therapeutic care, which included
oxygen intubation, remdesivir, levofloxacin (an antibiotic for
protection against secondary bacterial infections), dexamethasone (an
anti-inflammatory) and enoxaparin (an anticoagulant).
In the standard care only group, 13 of the 76 patients died (17.1%),
compared to just one of the 82 patients (1.2%) who received melatonin in
addition to everything else. That’s a reduction in mortality of 93%,
which is quite remarkable. Three mechanisms of action responsible for
this success appears to be a combination of its antioxidant,
anti-inflammatory and immunoregulatory activities.24
During the second week of infection, a time when severely infected
patients can take a drastic turn for the worse, the melatonin group
fared much better than the standard care only group, with only two
patients developing sepsis, compared to eight in the standard care only
group.25
The Hasan trial also supports findings from a clinical case series26
published in 2020, where patients diagnosed with COVID-19 pneumonia
received 36 mg to 72 mg of melatonin intravenously per day, in four
divided doses, as an adjunct therapy to standard of care.
All of the patients given melatonin improved within four to five
days, and all survived. On average, those given melatonin were
discharged from the hospital after 7.3 days, compared to 13 days for
those who did not get melatonin.
How Melatonin Prevents Sepsis
This isn’t the first time melatonin has been highlighted for its ability to prevent and treat sepsis. A 2010 paper27 in The Journal of Critical Care noted that melatonin helps prevent and reverse septic shock symptoms by:28
- Decreasing synthesis of proinflammatory cytokines
- Preventing lipopolysaccharide (LPS)-induced oxidative damage, endotoxemia and metabolic alterations
- Suppressing gene expression of the bad form of nitric oxide, inducible nitric oxide synthase (iNOS)
- Preventing apoptosis (cell death)
Similarly, a 2014 study29
in the Journal of Pineal Research pointed out that melatonin
accumulates in mitochondria, and has both antioxidant and
anti-inflammatory activity that could be useful in the treatment of
sepsis.
This was a Phase 1 dose escalation study in healthy volunteers to
evaluate the tolerability and health effects of melatonin at various
dosages. They also assessed the effect of melatonin in an ex vivo whole
blood model mimicking sepsis.
No adverse effects were reported for dosages ranging from 20 mg to
100 mg, and the blood model testing revealed melatonin and its
metabolite 6-hydroxymelatonin “had beneficial effects on sepsis-induced
mitochondrial dysfunction, oxidative stress and cytokine responses …”
The authors further explained:30
“Mitochondrial dysfunction initiated by oxidative
stress drives inflammation and is generally accepted as playing a major
role in sepsis-induced organ failure. It has been recognized that
exogenous antioxidants may be useful in sepsis, and more recently, the
potential for antioxidants acting specifically in mitochondria has been
highlighted.
We showed previously that antioxidants targeted to
mitochondria, including melatonin, reduced organ damage in a rat model
of sepsis ... In vitro models of sepsis show that melatonin and its
major hydroxylated metabolite, 6-hydroxymelatonin, are both effective at
reducing the levels of key inflammatory cytokines, oxidative stress,
and mitochondrial dysfunction.
In rat models of sepsis, melatonin reduces oxidative damage and organ dysfunction and also decreases mortality.
The dose needed for antioxidant action is thought to
be considerably higher than that given for modulation of the sleep–wake
cycle, but the actual dose required in man is unclear, particularly
because the major bioactive effects of oral melatonin in the context of
inflammation are likely to be mediated primarily by metabolite levels.”
Melatonin Has Many Mechanisms of Action
When it comes to viral infections, melatonin doesn’t actually target
the virus itself. It primarily aids the host, lowering the overreaction
of the host cells to the pathogen, thereby raising the host’s tolerance
to the virus. As explained in the featured Melatonin Research
commentary,31
“This tolerance allows the host sufficient time to develop the adaptive
immune response and finally eradicate the invading pathogens.”
By regulating your immune responses, melatonin also helps prevent cytokine storms,32
which is what ultimately kills some patients with serious SARS-CoV-2
infection. Melatonin is also a known cytoprotector with neuroprotective
properties that can potentially reduce the neurological sequelae
documented in patients infected with COVID-19.33
Part of melatonin’s benefit against COVID may also have to do with the fact that it enhances vitamin D signaling34
and, together, melatonin and vitamin D synergistically enhance your
mitochondrial function. In fact, your mitochondria are the final common
targets for both.35
I’ve written many articles detailing the importance of vitamin D
optimization to prevent SARS-CoV-2 infection and more serious COVID-19
illness. The evidence for this is frankly overwhelming, and raising
vitamin D levels among the general population may be one of the most
important prevention strategies available to us. To learn more, download
my vitamin D report, available for free on stopcovidcold.com. Melatonin may also combat SARS-CoV-2 infection by:36
Having an antibacterial effect on white blood cells called neutrophils37 (a high neutrophil count is an indicator for infection) |
Suppressing oxidative stress38 |
Regulating blood pressure (a risk factor for severe COVID-19) |
Improving metabolic defects associated with diabetes
and insulin resistance (risk factors for severe COVID-19) via
inhibition of the renin-angiotensin system (RAS) |
Protecting mesenchymal stem cells (MSCs, which have
been shown to ameliorate severe SARS-CoV-2 infection) against injuries
and improving their biological activities |
Promoting both cell-mediated and humoral immunity |
Promoting synthesis of progenitor cells for
macrophages and granulocytes, natural killer (NK) cells and T-helper
cells, specifically CD4+ cells |
Inhibiting NLRP3 inflammasomes39
— Inflammasomes are part of your natural immune response. When a
pathogen is detected, inflammasomes are activated and start releasing
proinflammatory cytokines. The inflammasome NLRP3, specifically, has
been identified as a key culprit in acute respiratory distress syndrome
(ARDS) and acute lung injury, both of which are potential outcomes of
COVID-19 infection40 |
Melatonin Reduces Risk of Positive COVID-19 Test
Data41,42
from Cleveland Clinic also supports the use of melatonin. Here, the
researchers analyzed patient data from the Cleveland Clinic’s COVID-19
registry using an artificial intelligence platform designed to identify
drugs that may be repurposed.43,44
By identifying clinical manifestations and pathologies shared by
COVID-19 and 64 other diseases, they were able to conclude that certain
proteins associated with chronic diseases are highly connected with
SARS-CoV-2 proteins. Put another way, a number of proteins appear to
play a key role in the pathologies seen both in COVID-19 and other
chronic diseases.
These connections suggest that drugs already in use for a chronic
disease may be repurposed and used in the treatment of COVID-19, as it
acts on one or more shared biological targets. Melatonin stood out in
this regard. Patients who used melatonin as a supplement had, on
average, a 28% lower risk of testing positive for SARS-CoV-2. Blacks who
used melatonin were 52% less likely to test positive for the virus.
Unfortunately, two key data points missing from the analysis are the
dosage used and the length of supplementation. These data were not
included in the patient registry, so we don’t know how much melatonin is
required, or how long you need to take it, to lower your risk of
SARS-CoV-2 infection to the degree found in this study.
Melatonin Is an Integral Part of Front Line Protocol
Early in 2020, the Front Line COVID-19 Critical Care Alliance (FLCCC)45 developed preventive, outpatient treatment and inpatient protocols46 based on the insights of the founding critical care doctors. Dr. Paul Marik,47 a critical care doctor known for his life-saving vitamin C sepsis protocol,48 is one of those doctors.
Marik published a paper in the Journal of Thoracic Disease in February 202049
giving the scientific rationale for using melatonin to help regulate
the oxidative imbalance and mitochondrial dysfunction that are commonly
found in sepsis.
This was followed by a paper published in the Frontiers in Medicine in May 2020,50
in which he and a team of scientists presented a therapeutic algorithm
for melatonin in the treatment of COVID-19 specifically. “Melatonin's
multiple actions as an anti-inflammatory, antioxidant and antiviral
(against other viruses) make it a reasonable choice for use,” they
wrote.
Based on its known mechanisms of action, the FLCCC has included
melatonin in its early treatment and hospital treatment protocols from
the start. You can download the latest protocols on the FLCCC’s website.51
As a supportive therapy, the FLCCC recommends taking 6 mg before bed
if you’re treating early or mild symptomatic COVID-19. The hospital
treatment protocol calls for anywhere from 6 mg to 12 mg of melatonin at
night, until discharge.
For patients treating long-haul COVID-19 syndrome (LHCS), they
recommend taking between 2 mg and 12 mg nightly. Begin with a low dose
and work your way up as tolerated. If your sleep is disturbed, lower
your dose. (Low doses of melatonin will help make you sleepy, while
higher doses can trigger sleeplessness.)
General Guidance for Supplementation
While the doses suggested when used against COVID are significantly
higher than what you’d normally take to improve your sleep, there does
not appear to be any danger to these doses. Research has found no
adverse effects for dosages ranging from 20 mg up to 100 mg.52
These dose ranges are up to 100 times more than what a typical
conservative dose of 0.5 mg, but it is encouraging that no adverse
effects were observed at these high doses. It would still be prudent
however to only use doses this high for limited times when you might
need them.
Whatever dose you take — and I recommend starting low, at 1 mg or
less — be sure to take melatonin at night, before bed. Rising melatonin
levels is the reason you feel sleepy in the evening, so it’s ill advised
to take it in the morning or during the day, when your natural level is
(and should be) low.
Melatonin is also best taken sublingually, either in the form of a
spray or sublingual tablet. Sublingually, it can enter your blood stream
directly and doesn’t have to go through the digestive tract. As a
result, its effect will be felt more rapidly.