To a degree, minoxidil response is dosage dependent. For example, 5% minoxidil generally grows more hair than 2%. But you can also apply 2% more liberally, or more frequently, and deliver a comparable daily dosage of minoxidil. While more minoxidil sometimes helps, beyond a certain threshold, additional minoxidil makes little if any difference. For more information on Rogaine, please read our Rogaine Product Review.