Topical Minoxidil: Regret, Stopping, and Restarting

What happens when you stop topical minoxidil?

The label answer is blunt. The men's 5% solution label and the women's 5% foam label both say continued use is necessary to increase and keep hair regrowth, or hair loss will begin again [1][2]. The directions describe continuous use only; neither label gives a tapering schedule [1][2].

The benefit therefore depends on continued application, and neither label names a point after which regrown hair stays.

Why people stop before the label checkpoint

A 2021 review in the Journal of the American Academy of Dermatology, written about oral minoxidil as an alternative, opens by noting that many patients are poorly compliant with topical minoxidil. It names the need to apply it twice a day, undesirable hair texture, and scalp irritation [5].

Scalp irritation has trial numbers behind it. In a 48-week double-blind trial of 393 men, 5% solution twice daily beat 2% solution and placebo on nonvellus hair count, with more pruritus and local irritation with 5% [6]. In a matching 48-week trial of 381 women, 5% was superior to placebo on all three primary measures, with more pruritus, irritation and hypertrichosis than 2% or placebo [7]. In a 16-week trial of 352 men, 5% foam, which uses a propylene glycol-free vehicle, increased hair counts versus placebo (P<.0001) [8].

The labels say to stop use if scalp irritation or redness, or unwanted facial hair growth, occurs. They also say not to use the product on a scalp that is red, inflamed, infected, irritated or painful [1][2].

How long should you give it before calling it a failure?

The men's 5% solution label says results may occur at 2 months with twice-daily use and that some men may need at least 4 months. It tells users to stop use if there is no regrowth in 4 months [1]. The women's 5% foam label says results may occur at 3 months with once-daily use and that some women may need 6 months. It uses 6 months as its no-regrowth checkpoint [2].

Those are label checkpoints, not trial endpoints. The men's and women's 5%-versus-2% solution trials each ran 48 weeks [6][7]. The men's foam trial ran 16 weeks and collected no efficacy data past that point [8].

Both labels also say that using more or more often will not improve results [1][2].

What about the shed people describe in the first weeks?

Neither label lists temporary shedding among its reasons to stop use. The stop-use lists name scalp irritation or redness, unwanted facial hair growth, chest pain, rapid heartbeat, faintness, dizziness, sudden unexplained weight gain, and swelling of the hands or feet [1][2]. The labels also note that some people have experienced changes in hair color or texture [1][2].

Restarting after a break

Neither label describes restarting after a break. The directions are written for continuous use: 1 mL of 5% solution twice daily for men, or half a capful of 5% foam once daily for women [1][2]. The facts available here include no study measuring how much regrowth returns after a gap, or how quickly.

If the routine is what you regret, not the drug

A 2021 review of 17 studies covering 634 patients concluded that oral minoxidil appears effective and well tolerated in healthy patients who struggle with topical use. It also said larger randomized dose-comparison studies were needed [5]. Minoxidil tablets are FDA-approved only for severe hypertension, and the tablet label states that use of minoxidil, in any formulation, to promote hair growth is not an approved indication [9].

The head-to-head data against topical are close. In a double-blind trial at one clinic in Brazil, 90 men with androgenetic alopecia were randomized to oral minoxidil 5 mg daily or topical 5% twice daily for 24 weeks, and 68 completed. The between-group differences were not statistically significant: frontal terminal hair density 3.1 hairs/cm2 (95% CI -18.2 to 21.5; P=.27) and vertex 23.4 hairs/cm2 (95% CI -0.3 to 43.0; P=.09) [10]. A second trial of 65 patients found that both 1 mg/day oral and 5% topical improved hair diameter over 6 months (P<0.001), with no significant difference between groups [11].

Low-dose oral minoxidil has its own trade-offs. In a retrospective multicenter study of 1404 patients treated for at least 3 months, with no control group, hypertrichosis occurred in 15.1% and led to withdrawal in 14 patients (0.5%). Other effects were lightheadedness 1.7%, fluid retention 1.3%, tachycardia 0.9%, headache 0.4%, periorbital edema 0.3% and insomnia 0.2%. Systemic effects led 29 patients (1.2%) to stop [12].