I just used peppermint oil the other day for a headache, mixed it with coconut oil and applied it to the temples.
Within 10 minutes my headache went down 50% and went away with 45 minutes.
I was impressed, first time doing it.

i also do that for headaches and it helps. thats amazing

Interesting. I would not apply peppermint oil to the skin and/or scalp neat (undiluted). Best to mix with a carrier oil, like jojoba, before application.

And your post was a sync for me as I just saw this article today:
Does Peppermint Oil Work for Irritable Bowel Syndrome?

https://media.mercola.com/ImageServer/Public/2023/May/PDF/peppermint-oil-irritable-bowel-syndrome-pdf.pdf

Here is the accompanying video:
Peppermint Oil for Irritable Bowel Syndrome
https://www.youtube.com/watch?v=LgiYwxTI0Ks&t=22s