There is no evidence that it is unsafe in lupus: read on!
Why do people with lupus think it is unsafe to take melatonin?
It is because there are outdated websites and patient education pages that state this. It even occurs on highly-acclaimed sites such as the Mayo Clinic.
How can the Mayo Clinic be wrong?
Most likely: there are tons of patient education pages that were produced a long time ago.
There is probably no one who polices and up dates them.
Certainly the doctors are way too busy to do this: they are taking care of patients and doing research.
Theoretically, melatonin may improve the immune system in lupus
and other autoimmune diseases
- One problem in lupus is that there are lower numbers of important white blood cells called Tregs (regulatory T-cells).
- Tregs help to normalize the immune system and prevent overactivity.
- With less Tregs, bad B-cells that make dangerous lupus autoantibodies (such as anti-dsDNA) can live a very long time (and even forever, "immortal").
- Melatonin does effect the immune system. One of the things it can do is increase these important Tregs that could be helpful in lupus and other autoimmune diseases
- The 2013 research article referenced below by Lin GJ et al and the 2019 article by Zhao et al go into detail about this
What happens to lupus mice when they are given melatonin
- When melatonin is given to female mice that are prone to getting lupus, it prevents them from getting lupus!
- This was shown in a 2010 study by Zou LL et al and another in 2008 by Jimenez-Caliani AJ et al (referenced below)
How about humans?
- There are no studies of using melatonin in people with lupus.
- This is a huge reason why it is incorrect to tell people with lupus not to use melatonin. There is no evidence to support that recommendation.
- However, there is a study in people with rheumatoid arthritis (a related autoimmune disease).
- Melatonin did NOT worsen rheumatoid arthritis in these patients (Maestroni et al, referenced below)
I do not ask my patients with lupus to avoid melatonin.
There is actually more evidence that it may be beneficial rather than harmful.
Lupus patient education websites should remove their recommendations to avoid melatonin.
These sites and pages are outdated.
Note that Dr. Thomas' posts are for informational purposes only, and are not meant to be specific medical advice for individuals. Always seek the advice of your healthcare provider with any questions regarding your own medical situation.
DONALD THOMAS, MD