Is it really okay to wash out minoxidil after 4 hrs?

[bluechips]

Rogaine says that you can wash out the rogaine after 3-4 hrs (and Dr. Lee says even less time is okay for his minoxidil)- once it is absorbed into the scalp, is the minoxidil not affected by washing or anything? What I basically want to know is: is there any difference between washing 4 hrs after putting on minoxidil and washing 12 hrs after putting it on.
Thanks.

 

[grabber]

I assume it take somewhere around 4 hrs to dry what ever you've applied. After that, it doesnt really bother if you shower or not since the skin has absorbed all it could

 

[CCS]

maybe a very small amount would be extracted out of the scalp with shampoo, but I think minoxidil is not that soluble in water, so it should not be an issue. The main factor is that before 4 hours and especially before 2 hours, your scalp is still absorbing minoxidil off the surface of the skin, through the pores. If you wash it off, you stop absorption.

Since 2% minoxidil works, so would getting a little less than the max dose with 5%. leaving in on 4 hours just gives you the most for your money, though you get most of that in just 2 hours. 2 hours of 5% is definitely much better than 4 hours of 2%. There could be a time release factor, but I think that unlike finasteride which bonds to serum proteins, minoxidil goes into blood vessel walls, so it should stay there a while even if you don't have more on the surface. Obviously it must leave the vessels too, or degrade, so leaving it on your scalp does help with the time release. But I don't think you need to leave it on that long unless you just want the most for your money.