How long does it take for hair loss to revert after stopping Minoxidil?

Combination therapy works better than monotherapy. If the Minoxidil is performing well,I would continue it and add the PRP and LLLT. This should give you better density and thickness of hair shafts as well as decrease the possibility of shed from discontinuation of Minoxidil. Should you decide to stop the Minoxidil, it will usually take 6 to 9 months to see negative changes. Find a hair expert.
Jeff Rapaport MD FAAD
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Please make sure you discuss this strategy with your dermatologist before going this route. While minoxidil works by elongating the anagen (growth) phase of the hair follicle, PRP delivers growth factors to promote vascularization and elongation of the the hair follicle. The mechanisms are different and I would not advise attempting to substitute an adjunctive treatment like PRP for minoxidil which has a long history of being a first line treatment for androgenetic alopecia. You might get away with it. But the more likely scenario is that you will in fact experience a shed and lose the hair that you were retaining by using minoxidil consistently. And you may not get it back. If application of minoxidil is a hassle, and it is for many patients, consider switching to low dose oral minoxidil once a day. It is generally very well tolerated (provided there are no preexisting cardiovascular issues) and, at appropriate doses, has equivalent efficacy to 5% minoxidil applied twice daily. Good luck!