Hair follicles grow through cycles of development alternating between growth and dormant stages. The dormant follicles lie scattered across the scalp and are hence not noticed.

However, it has been noticed in men as well as 生髮藥 women that the dormant follicles are arranged together around the central part of the head or before the scalp, merely above the head.

Minoxidil may stimulate growth although it may take time for follicles to emerge from their dormant stage which is why the effects may not be initially noticed.