Minoxidil is something that may work really well, barely or not at all. Point is, the results vary widely per individual. The most recent long-term study I know of is the Olsen et al. (1990). According to their five-year study, regrowth peaks after 1 year. At the third year, there was a slight decrease in nonvellus hairs, albeit not significant. At the 4.5 to 5 years, further decrease was noticed. But this was just on average. There were individuals that still had additional regrowth even at the 5 year mark.
The citation of this study tells us the following (somewhat more elaborate than I state above):
"Patients who completed the long-range follow-up were not
statistically different in terms of baseline age, duration,
or pattern of baldness from the larger initial group (p> 0.15).
The patients who continued with topical minoxidil for
4.5 to 5 years tended to have
lower baseline nonvellus hair counts (p =0.076)
than the short-term group but had a similar amount
of hair growth during the initial 12 months
(p == 0.360).
Hair regrowth with topical minoxidil peaked at
approximately 1 year of treatment with a slight but
not statistically significant decrease in 1-year counts
seen at the 3-year visit (p =0.16, Fig. 2). At 1 year
there was a mean increase in nonvellus hairs compared
with the baseline count of 273.4 (± 157.1) and
that at 3 years, 246.2 ( ± 171.8). At 4.5 to 5 years a
further decrease was noted in the mean nonvellus
hair counts (Table II), which was a statistically significant
decrease from the 1-year nonvellus hair
counts (p == 0.012) but was still a significant
(p <0.001) increase over the baseline count
(206.6 ± 163.3). However, some patients receiving
long-term treatment with topical minoxidil continued
to have an increase in nonvellus target area
counts at 4.5 to 5 years beyond their 1-year counts
(n =9). Similarly, a few subjects, despite continued
treatment with topical minoxidil, had nonvellus target
area hair counts decrease below baseline (n = 4,
-36 ± 40.5).
"
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Minoxidil is something that may work really well, barely or not at all. Point is, the results vary widely per individual. The most recent long-term study I know of is the Olsen et al. (1990). According to their five-year study, regrowth peaks after 1 year. At the third year, there was a slight decrease in nonvellus hairs, albeit not significant. At the 4.5 to 5 years, further decrease was noticed. But this was just on average. There were individuals that still had additional regrowth even at the 5 year mark.
The citation of this study tells us the following (somewhat more elaborate than I state above):
"Patients who completed the long-range follow-up were not
statistically different in terms of baseline age, duration,
or pattern of baldness from the larger initial group (p> 0.15).
The patients who continued with topical minoxidil for
4.5 to 5 years tended to have
lower baseline nonvellus hair counts (p =0.076)
than the short-term group but had a similar amount
of hair growth during the initial 12 months
(p == 0.360).
Hair regrowth with topical minoxidil peaked at
approximately 1 year of treatment with a slight but
not statistically significant decrease in 1-year counts
seen at the 3-year visit (p =0.16, Fig. 2). At 1 year
there was a mean increase in nonvellus hairs compared
with the baseline count of 273.4 (± 157.1) and
that at 3 years, 246.2 ( ± 171.8). At 4.5 to 5 years a
further decrease was noted in the mean nonvellus
hair counts (Table II), which was a statistically significant
decrease from the 1-year nonvellus hair
counts (p == 0.012) but was still a significant
(p <0.001) increase over the baseline count
(206.6 ± 163.3). However, some patients receiving
long-term treatment with topical minoxidil continued
to have an increase in nonvellus target area
counts at 4.5 to 5 years beyond their 1-year counts
(n =9). Similarly, a few subjects, despite continued
treatment with topical minoxidil, had nonvellus target
area hair counts decrease below baseline (n = 4,
-36 ± 40.5)."