people have been referring to forskolin increasing melanin. I might have found an interesting article on that:

It looks like an eyelash serum formula increases the pigmentation of the follicles:

http://www.beautydebutante.com/2010/09/talika-lipocils-expert-eyelash-enhancer-growth-serum-review/ -

I think this could be promising to see what ingredients help to penetrate. Of course a small eyelash tool is not big enough ( and I read as forskolin is only one of the many ingredients, the effect will be even greater with a higher dose) for those wanting to darken their hair/skin

But it would be interesting to look into the ingredients to help formulating our own melanin lotion ( many of those ingredients have nothing to do with penetration, so we can skip them)

PS: here’s a pubmed article the lady is probably referring to:

http://www.ncbi.nlm.nih.gov/pubmed/19054056 -