I can get 1.5ml to cover all of my problem areas. Lots of people use 2ml and I know some go crazy with like 5ml but only once a day. With the foam I don’t even measure som I’m pretty I’m sure I’m greatly overdosing but I don’t use it very often.
I think you should experiment until you find the right amount. Any more than .5ml on my crown and that sh*t starts to drip all down the back of my head but I’m also not thinning as bad as some are in that area. I don’t think your scalp needs to be soaking with the stuff especially if you’re rubbing it in or derma rolling for absorption. Also something like 10% goes systemic anyway so it kind of permeates throughout the scalp. Hope that helps some.