Melatonin megadoses?

#387

you mean mg of melatonin, you will not feel well with 600g… LOL. I am overweight and my lowest heart rate is 46. But everyone is different.

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#388

@Beth With age, body makes less melatonin, which I understand, and to take some melatonin to replace what’s lacking makes sense to me. However, taking anything in great excess makes that lacking chemical a strong medication, the mechanism of action of which is not fully understood as I read about it. So, I asked ChatGPT about possible complications of taking mega doses of Melatonin.

Taking mega doses of melatonin (far beyond the commonly recommended 0.5–5 mg range) on a regular basis can lead to a variety of short- and long-term complications, even though melatonin is generally considered safe in small doses for short-term use. Here’s a breakdown of potential complications:

1. Hormonal Disruption

Melatonin is a hormone, and taking large doses regularly can interfere with your body’s natural hormonal rhythms. This might affect:

  • Reproductive hormones, potentially impacting fertility (especially in women).
  • Puberty onset in adolescents.
  • Menstrual cycle irregularities.

2. Sleep-Wake Cycle Disruption

Ironically, too much melatonin can throw off your circadian rhythm:

  • You may start to feel groggy during the day and wide awake at night.
  • Over time, your natural melatonin production could downregulate, making sleep harder without the supplement.

3. Mood and Cognitive Effects

Excess melatonin might contribute to:

  • Depression or low mood.
  • Brain fog or difficulty concentrating.
  • Increased daytime drowsiness or sluggishness.

4. Drug Interactions & Health Risks

High doses of melatonin can interact with:

  • Blood thinners (e.g., warfarin): increased bleeding risk.
  • Immunosuppressants: may interfere with immune function.
  • Diabetes medications: may affect blood sugar control.
  • Seizure medications: can increase risk of seizures in some people.

5. Headaches, Dizziness, and Nausea

Common side effects at higher doses:

  • Headaches
  • Dizziness
  • Nausea
  • Vivid dreams or nightmares

6. Tolerance and Dependency

While melatonin isn’t typically considered addictive, using large doses frequently can lead to:

  • Psychological dependence (“I can’t sleep without it”).
  • Reduced effectiveness over time (needing more to get the same effect).

It was enough for me not to take mega doses or even take it consistently every night. Logically, I cannot agree with taking anything in great excess.

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#389

Citing ChatGPT without providing sources is not very valuable. I’m not sure the point as backed by science other than fertility and puberty: these are really important ones with many papers on it.

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#390

The problem with the phrase possible complications is that it comes up with masses of things. I have been on over a gram of melatonin a night for over a year and as far as I am concerned I intend to continue with this.

I have been doing a weekly blood panel now for almost 3 years whilst varying at lot of what I do and have identified only positives from Melatonin.

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#391

Melatonin’s role in delaying puberty is part of what it does. It holds back damage to mitochondrial DNA which delays the development clock (in my hypothesis of what the development clock is).

For example where girls have Hypothalamic hamartomata you get a reduction in melatonin and precocious puberty.

That is not a bad side effect of melatonin it is one of its functions in the body. As far as I am concerned aged as I am 65 I don’t expect to go through puberty in reverse as a result of taking melatonin.

In fact because puberty is an interplay between mRNA splicing changes and hormonal changes I think it would be hard to reduce fully even by turning the development clock right back.

Melatonin’s effects on fertility are more complex and it is probably best timed to suit ovulation and protection of both the ovaries and the eggs.

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#392

You are right. I erased links to the papers to make it shorter :grinning: silly me. Melatonin dosing is not well researched unfortunately.

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#393

Just seing this study now, the RRs are crazy good: “melatonin use was associated with a reduced risk of developing AMD (RR, 0.42; 95% CI, 0.28-0.62) […] melatonin was associated with a reduced risk of AMD progression to exudative AMD (RR, 0.44; 95% CI, 0.34-0.56)”.

This paper is cited in: Melatonin protects retinal pigment epithelium cells against ferroptosis in AMD via the PI3K/AKT/MDM2/P53 pathway 2025

And in Melatonin stabilizes atherosclerotic plaques: an association that should be clinically exploited 2024. @AnUser, is it clinically relevant?

On AMD and PD:

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#394

Looks like mechanistic speculation, so not at all.

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#395

I wasn’t sure which thread to put this under so l figured this is as good as any.

I have been using high doses of melatonin (100 to 500 mg and more) since September 2024. I have had weird nerve pain problems for at least the last 5 years (mainly sciatic but others too). Anytime l would bend down to pick something up l ran the risk agitating the nerve and it could last 2 to 6 weeks. During the day easily dealt with but at night it would make it almost impossible for me to sleep.

Around December l started noticing my nerves seemed to be becoming more resilient. I pushed it a bit too hard in February 2025 and had a 3 week stint of pain but other than that it seemed to be getting progressively better even now.

I have done exercises in the past and if l pushed a little too much it could cause a flare up.

To be completely upfront, as stated previously l am performing many interventions including rapa and it could be all interventions synergistically or none at all but l attribute these positive effects to the melatonin.

I still have a fair amount of issues that l am trying
to address but to paraphrase Dr. Reiter “melatonin is pretty good”.

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