The evidence
Combining Minoxidil and Red Light Therapy
Two randomised controlled trials tested minoxidil and red light therapy separately, then together. Both times the combination won, and it got there in half the time. Minoxidil goes on first, red light second.
The short answer
Yes, and the trial evidence suggests you should. In two randomised controlled studies, minoxidil alone and red light therapy alone produced comparable results. The groups using both did better than either on its own, and reached a measurable increase in regrowing follicles at two months where the single treatment groups took four.
Apply minoxidil to a dry scalp, let it absorb for 20 to 30 minutes, then run your light session. With The RedLight Hat Pro that is 15 minutes.
01 · The trial
What the study actually tested
A randomised controlled trial published in Lasers in Surgery and Medicine in 2017 split 45 women with pattern hair loss into three equal groups and followed them for four months. Minoxidil, sold in the United States as Rogaine, is a topical treatment applied directly to the scalp.
Study design
45 women, split evenly into three arms
15
15
15
Progress was measured three ways: clinically, by dermoscopy, and by ultrasound bio-microscopy.
The light arm delivered red light across the whole scalp, in the same red band the RedLight Hat Pro uses. This trial ran in women. The men's evidence is further down.
02 · The result
Everyone got there. One group got there first.
By four months, all three groups showed a significant increase in regrowing hair follicles. That is the part most summaries stop at, and it makes the three look interchangeable. They were not.
Time to a significant increase in regrowing follicles
Two months ahead of either treatment on its own
The combination group also ranked highest on the Ludwig severity scale and on patient satisfaction. Hair diameter increased in all three groups, but not by enough to be statistically meaningful in any of them. Chart is illustrative; the study reports timing, not hair counts.
The combination did not grow more hair. It got to the same place in half the time.
A second trial found the same thing
Three years later a separate team ran the same three-way comparison on twice the number of patients. The combination group again came out ahead of either treatment on its own, this time on both hair density and hair thickness. No side effects were reported in either trial.
Two trials, same conclusion
Two independent teams, in two different countries, five years apart. Both found the combination beat either treatment used alone.
03 · Men
What the evidence shows in men
Red light therapy has been tested in men directly, in a multicentre, randomised, double-blind trial against an inactive placebo. 128 men and 141 women treated the whole scalp three times a week for 26 weeks.
Terminal hairs gained per cm², 26 weeks
Red light therapy compared against an inactive placebo
The researchers reported that the increase in terminal hair density was independent of the age and sex of the subject.
Men gained nearly three times what the placebo group gained. Separately, a review of thirteen clinical trials concluded that red light therapy is effective for pattern hair loss in both men and women, and can be used either on its own or alongside minoxidil.
The two combination trials above ran in women, so the specific finding about speed comes from female pattern hair loss. The mechanism it relies on is described below, and there is nothing about it that is sex specific.
04 · The mechanism
Why combine minoxidil and red light therapy?
They are not doing the same job twice. Each acts on a different part of the same problem, which is why stacking them makes sense rather than simply doubling up.
Minoxidil
Opens the supply line
A topical vasodilator. It widens the blood vessels feeding the follicle and pushes resting follicles back into their growth phase. Well established, and one of the few hair loss treatments with regulatory approval behind it.
TripleWave
Powers the follicle
Light at specific red wavelengths is absorbed by the mitochondria inside follicle cells, raising the energy available for the cell to do its work. It also lowers inflammation around the follicle.
Diagrams are illustrative and not to scale.
05 · The stack
What each one adds to the other
- Delivery plus capacity. Minoxidil improves what reaches the follicle. Light therapy raises what the follicle can do with it. One is supply, the other is capability.
- A calmer scalp. Red light reduces inflammation around the follicle, and an irritated scalp is one of the common reasons people abandon minoxidil in the first few weeks.
- Speed, which is the real finding. Both treatments reached the same place by four months. Only the pair reached it by two.
Why speed matters
Most people stop treating hair loss before anything becomes visible. Halving the wait to a measurable change is worth more than it sounds.
06 · The routine
Minoxidil before or after red light therapy?
Minoxidil goes on first, red light second. You can do both in the same sitting, but not at the same time. The whole thing takes about 45 minutes and most of it is waiting.
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Step one · 0 min
Apply to a dry scalp
Minoxidil goes on dry hair and skin. Wet hair dilutes it and carries it away from where you want it.
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Step two · 20 to 30 min
Let it absorb
No washing, no styling products, no other topicals in this window.
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Step three · 15 min
Run your light session
With The RedLight Hat Pro that is 15 minutes a day, seven days a week. Putting the hat on before the minoxidil has absorbed traps product against the inside of it.
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Then keep going
Give it four months
The trial measured at two months and four. Nothing meaningful is visible before that, in this study or any other.
The light half of the routine
The RedLight Hat Pro
TripleWave™ Tech. 125 diodes across 615, 635 and 650 nanometres, covering the whole scalp in one 15 minute session.
See the spec and price15 min a day · 90 day results · One time purchase
07 · Common questions
Questions people ask about running both
Can you use minoxidil and red light therapy together?
Yes. Two randomised controlled trials tested exactly that and both found the combination outperformed either treatment used on its own. No side effects were reported in either trial.
Should minoxidil go on before or after red light therapy?
Before. Apply minoxidil to a dry scalp, give it 20 to 30 minutes to absorb, then run your light session. Doing it the other way round means the light is passing through wet product rather than reaching the scalp.
Can I use them at the same time?
Not in the same moment. Putting the hat on while the minoxidil is still wet traps the product against the inside of it, which wastes the dose and makes the hat harder to keep clean. Wait for it to dry.
How long after applying minoxidil can I use red light therapy?
20 to 30 minutes is enough for it to absorb. There is no benefit to waiting longer than that, and no need to rinse anything off first.
Does red light therapy work better than minoxidil?
In the trials above, neither beat the other. Used alone, minoxidil and red light therapy reached comparable results by four months. The difference showed up when they were used together.
How long before I see anything?
The combination group showed a measurable increase at two months. Either treatment on its own took four. Nothing meaningful is visible before two months in this study or any other.
Do I have to keep using minoxidil once I have a light device?
The trials tested them as a pair, not as a handover. Stopping minoxidil means you are back to a single treatment, which the same trials show is slower.
Sources
Esmat SM, Hegazy RA, Gawdat HI, Abdel Hay RM, Allam RS, El Naggar R, Moneib H. Low level light-minoxidil 5% combination versus either therapeutic modality alone in management of female patterned hair loss: a randomized controlled study. Lasers in Surgery and Medicine, 2017;49(9):835-843. https://doi.org/10.1002/lsm.22684
Liu Y, Jiang LL, Liu F, Qu Q, Fan ZX, Guo Z, Miao Y, Hu ZQ. Comparison of low-level light therapy and combination therapy of 5% minoxidil in the treatment of female pattern hair loss. Lasers in Medical Science, 2021;36(5):1085-1093. https://doi.org/10.1007/s10103-020-03157-1
Jimenez JJ, Wikramanayake TC, Bergfeld W, Hordinsky M, Hickman JG, Hamblin MR, Schachner LA. Efficacy and safety of a low-level laser device in the treatment of male and female pattern hair loss: a multicenter, randomized, sham device-controlled, double-blind study. American Journal of Clinical Dermatology, 2014;15(2):115-127. https://doi.org/10.1007/s40257-013-0060-6
Darwin E, Heyes A, Hirt PA, Wikramanayake TC, Jimenez JJ. Low-level laser therapy for the treatment of androgenic alopecia: a review. Lasers in Medical Science, 2018;33(2):425-434. https://doi.org/10.1007/s10103-017-2385-5
All retrieved via PubMed.
Medically reviewed
Celestine Gitau, Certified Trichologist (IAT)
Celestine is a certified trichologist and cosmetic chemist who has worked with patients for over seven years. She has taught at the Institute of Trichologists in the UK, spoken at global conferences, and published in international journals.
The RedLight Hat Pro
TripleWave Tech. 15 minutes a day. 125 TripleWave diodes across 615, 635 and 650 nanometres.
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