The most effective strategy for managing androgenetic hair loss is one that most patients do not pursue — starting treatment early, before significant loss has occurred. Understanding why early intervention produces better long-term outcomes changes the way the treatment decision should be framed.
Finasteride works by reducing DHT and thereby slowing or halting the miniaturisation process. The follicles that respond best to this intervention are those that are in the early phases of miniaturisation — still producing visible, if slightly finer, hairs. Follicles that have already been miniaturised to the point of producing only vellus hairs, or that have been dormant for years, have a much lower probability of responding meaningfully.
This means the window of maximum therapeutic efficacy for finasteride is earlier than most patients realise — ideally starting at Norwood 2 to 3, when the loss is visible but the follicles are still biologically active and responsive. Starting at Norwood 4 or 5 after years of progression treats a smaller proportion of viable follicles and produces a less impressive response.
Minoxidil similarly produces better responses when started early. The mechanism — stimulating follicle activity — works on follicles that are still active. Very long-established areas of baldness with no remaining follicular activity do not respond.
The framing shift: rather than asking whether treatment is worth it after significant loss has occurred, the more productive question is whether to start treatment at the first signs of recession — when the most follicles are still salvageable and the long-term outcome is most favourably influenced by intervention.
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