Comment by OutOfHere

The P5P form harms less if in excess. This is in contrast to the default form which is pyridoxine. I have found 20 mg of P5P twice daily to be quite useful for keeping stress spikes in check.

Regarding melatonin, newer data up to 2024 in https://pubmed.ncbi.nlm.nih.gov/38888087/ confirms that 4 mg is an optimal dose for sleep. For a discussion, search for this article on r/FoodNerds.