Finasteride is a medication prescribed for male pattern hair loss (androgenetic alopecia). This oral treatment works to counteract the progressive thinning and eventual loss of hair. It helps preserve existing hair and, in some cases, encourage new hair growth.
How Finasteride Works to Prevent Hair Loss
Finasteride functions by targeting a specific biological pathway involved in hair loss. It acts as an inhibitor of the enzyme 5-alpha-reductase. This enzyme is responsible for converting testosterone into dihydrotestosterone (DHT).
DHT is a more potent androgen that plays a central role in the miniaturization of hair follicles in individuals genetically predisposed to male pattern hair loss. When DHT binds to androgen receptors within hair follicles, it triggers a process where the follicles progressively shrink. This miniaturization leads to the production of finer, shorter, and less pigmented hairs over time, eventually causing the follicles to become dormant and cease hair production. By inhibiting 5-alpha-reductase, finasteride effectively reduces the levels of DHT in the scalp, thereby preventing or slowing this miniaturization process and allowing affected hair follicles to remain active and produce healthier hair.
What Happens When You Stop Finasteride
Discontinuing finasteride typically leads to a reversal of the hair benefits gained or preserved during treatment. The medication’s effects are dependent on continuous use, meaning that once the body no longer receives the active compound, its protective action against hair loss diminishes. Hair loss will generally resume its previous rate of progression.
The timeline for this resumption can vary, but many individuals begin to notice changes within several weeks to a few months after stopping. Clinical studies and observations suggest that significant hair loss often becomes apparent within three to twelve months, with hair counts potentially returning to pre-treatment levels within this period.
The body’s hormonal environment gradually reverts to its pre-finasteride state, as the medication is metabolized and cleared from the system. Finasteride has a relatively short half-life, meaning that much of the drug is cleared within 24 hours of the last dose, though its biological effects can persist for a few days to weeks. The benefits of DHT reduction will wane, allowing the underlying genetic predisposition to hair loss to manifest once more.
Why Hair Loss Resumes
The resumption of hair loss after finasteride discontinuation is a direct consequence of the medication’s mechanism of action. When finasteride is no longer present in the body, this inhibition ceases. As a result, the 5-alpha-reductase enzyme regains its full activity, leading to the renewed conversion of testosterone into DHT. DHT levels in the scalp, which were suppressed by the medication, begin to rise and return to their baseline concentrations.
This increase in DHT then re-engages with the androgen receptors within genetically susceptible hair follicles. The re-established presence of elevated DHT levels triggers the miniaturization process once more. Hair follicles that had recovered or maintained their size under finasteride’s influence will begin to shrink again, producing finer, weaker hairs. Over time, these follicles may cease hair production altogether, leading to progressive thinning and baldness, reflecting the natural course of androgenetic alopecia without intervention.
Managing Hair Loss After Discontinuation
For individuals who discontinue finasteride, various strategies exist to manage ongoing hair loss. One common option is topical minoxidil, an over-the-counter treatment that works by promoting blood flow to hair follicles and extending the hair growth phase. It is applied directly to the scalp and can help stimulate hair regrowth and slow down further shedding.
Another approach involves low-level laser therapy (LLLT) devices, which use specific wavelengths of light to stimulate cellular activity within hair follicles. These devices are non-invasive and can be used at home to support hair health. For more significant hair loss, surgical options such as hair transplantation may be considered. This procedure involves moving healthy hair follicles from areas of dense growth to balding or thinning regions of the scalp, offering a more permanent solution for restoring hair density.