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.

Concealers ( thin layered / thick layered ) always act as barriers..... The scalp should be cleaned properly before application of the minoxidil for better and proper absorption......you can apply concealer few minutes after minoxidil...

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