Can You Still Use Concealers While Trying To Regrow Hair?

[Hair2018]

A quick question - if I use products that are designed to regrow hair, can I still use hair fibres or powder concealers in the meantime, or do you have to stop using these in order to let the hair folicles 'breath' and allow hair to regrow? I'm thinking of trying stuff to regrow my hair, but what do I do in the meantime until it grows back? Obviously I can't walk around with my hair loss visibly on display.