Most minoxidil products on Amazon don't provide safety or side effect information.
January 2020 in “Journal of dermatology research and therapy” Most over-the-counter hair loss treatments lack strong evidence of effectiveness but cost nearly as much as the proven treatment, minoxidil.
3 citations,
December 2018 in “PubMed” Most over-the-counter hair loss treatments lack strong evidence of effectiveness and are not FDA-approved.
September 2023 in “Journal of the American Academy of Dermatology” Curly/coily hair products are more expensive than straight hair products.
Minoxidil and a solvent mixture can prevent hair loss caused by chemotherapy in mice.