Can I apply minoxidil while I am still having the hair concealer on my hair or the concelear will act like a barrier ??

In my opinion, any product or concealer that inhibits the absorption of the Rogaine will affect its usefulness. Try to avoid using concealer in this manner. Hair concealer should not have any effect on hair  regrowth. Please be gentle with the placement and removal of the concealer. Hope this helps. Good luck.

Minoxidil penetration is reduced by concealers. The minoxidil should be applied first followed by the concealer.

Minoxidil can be used with a concealer as the concealer should not interfere. Be sure to wash off the concealer prior to using minoxidl