Have you heard of topical minoxidil for hair loss? The vast majority of men and half of all women will suffer from pattern baldness in their lifetime. If you are considering using a topical product that contains minoxidil, we may have some crucial information for you before you use the medicine. Read on to learn more about the benefits, mechanisms, and drawbacks of topical minoxidil.
What is Minoxidil?
Minoxidil was originally developed as an oral medication. It widens blood vessels allowing its use as a treatment for hypertension .
Surprisingly, a study from 1972 showed that a major side effect of oral minoxidil was unexpected hair growth .
Mechanisms of Action
While the exact mechanism of how minoxidil stimulates hair growth is not fully understood, some of its molecular effects are :
- Minoxidil widens blood vessels (vasodilator) in the area where it’s applied. However, topical minoxidil doesn’t affect blood vessels throughout the body, diminishing its side effects [2, 6].
- Minoxidil relaxes the muscle of the blood vessels through the action of its sulfated metabolite (minoxidil sulfate) by opening potassium channels .
- By opening potassium channels and dilating blood vessels, minoxidil allows more blood, nutrients, and oxygen to reach the follicle, which promotes hair growth .
- Minoxidil increases keratin-associated proteins, which is associated with a positive response to the treatment [7, 8].
- Minoxidil decreases the expression (into proteins) of the epidermal differentiation complex and inflammatory genes, and other genes like matrix metallopeptidase 7 (MMP7) and LOC100506422, among others [7, 8]. Interestingly, the expression of many of these genes differs between the vertex and frontal scalp .
- Minoxidil also increases the vascular endothelial growth factor (VEGF), which is involved in hair growth .
There’s a sulfotransferase enzyme test that you can take (in plucked hair follicles) to predict if you’ll have a good response to topical minoxidil treatment .
Benefits Of Topical Minoxidil
1) Improves Hair Growth
Minoxidil is much less effective when there are large areas of hair loss. The vertex of the scalp is the area most likely to respond to treatment .
The growth also lasts only as long as treatment continues. Hair loss will begin again within months after stopping the use of minoxidil .
Topical minoxidil has proven to be slightly less effective in women, only re-growing hair in 40% of female users .
However, women who didn’t respond were treated with a novel 15% topical minoxidil solution and showed 60% improvement after 12 weeks without significant side effects .
2) Improves Male and Female Pattern Baldness (Androgenetic Alopecia)
Androgenetic alopecia, often referred to as male or female pattern baldness, affects up to 80% of men and 50% of women in the course of their life .
In women, it produces diffuse thinning of the crown region with the maintenance of the frontal hairline and can be a sign of increased male sex hormones. The male pattern is characterized by a bitemporal recession of the frontal hairline, followed by diffuse thinning at the vertex .
5% topical minoxidil treats androgenetic alopecia, with hair growth after 3-6 months. About 40% of patients experience hair regrowth .
3) Improves Alopecia Areata
Alopecia areata is an autoimmune disorder that can cause hair loss in children and adults .
Studies have shown that minoxidil can be used, often concurrently with or sequentially after another medicine, to treat this form of baldness .
A study found that 48 patients treated with 1% minoxidil foam showed a 38% improvement, while 47 patients treated with 5% minoxidil showed an 81% improvement .
Minoxidil can be used as a mono-therapeutic treatment, but also combines well with other treatments for patients suffering from alopecia areata .
4) Helps Hair Regrowth In Chemotherapy Patients
Chemotherapy-induced baldness can be treated with topical minoxidil, which accelerates the already occurring hair regrowth .
5) Accelerates Nail Growth
A pilot study had 32 women use 5% topical minoxidil on one finger each. The nails that were treated with minoxidil grew faster than those without .
Minoxidil may cause an allergic reaction that can lead to itching, hives, swelling, and/or difficulty breathing .
Other possible side effects include chest pain, dizziness or fainting, irregular heartbeat, severe itching, burning, or redness of scalp, sudden and unexpected weight gain, and swelling of the face, hands, or feet .
Less serious side effects may include a change in hair color or texture, dry, flaking, or red skin, and increased hair loss .
If you are pregnant or breastfeeding, have a history of heart disease, high blood pressure, or fluid retention, or have open wounds or irritation on your scalp, talk to your doctor before using minoxidil .
Topical minoxidil works better in larger concentrations. A study of 393 men showed that those who used 5% minoxidil experienced 45% more hair regrowth than those using 2% minoxidil or placebo. Those who used 5% minoxidil also had an earlier response to the medication .
Minoxidil Combined With Other Drugs/Treatments
A study of 45 patients showed that hair density can be maintained with 5% topical minoxidil fortified with 0.1% finasteride after initial treatment with 5% topical minoxidil and oral finasteride for 2 years.
Therefore, topical finasteride is useful for hair density maintenance after initial treatment with oral finasteride, avoiding its chronic use .
A study of 34 women found that topical minoxidil can be combined with 17α-Estradiol to improve female pattern hair loss treatment .
3) Platelet-Rich Plasma (PRP)
In a study of 25 patients, minoxidil in combination with PRP showed greater improvement than PRP with finasteride after 6 months of treatment .
4) Low-Level Light Therapy
A study of 45 women with hair loss found that low-level light therapy had comparable results to 5% minoxidil in the treatment. However, combined therapy had significantly better results .
5) UV Light
A study found that supplementing minoxidil treatment with UV light didn’t have a significant positive nor adverse effect on hair growth .
In an animal study, minoxidil 5% combined with tretinoin 0.1% was more effective than minoxidil alone in increasing hair growth and thickness .
Minoxidil Compared To Other Treatments For Hair Loss
Topical minoxidil and finasteride are the only treatments that have been FDA approved for the treatment of female pattern hair loss and androgenetic alopecia .
However, finasteride has been associated with side effects like decreased libido and gynecomastia .
A study of 450 patients concluded oral finasteride was superior to 5% topical minoxidil, while the combined treatment of the two was the most effective .
Topical cetirizine is another treatment for male pattern baldness (androgenetic alopecia) .
A study found that, like minoxidil, cetirizine increased hair density when tested against a placebo .
Cetirizine does not appear to show any notable side effects, whereas minoxidil has several known possible side effects .
3) 5-Alpha Reductase Inhibitors
Finasteride and dutasteride, 5-alpha reductase inhibitors, are first-line treatments for male pattern baldness .
Also, topical minoxidil can be precisely applied to a desired area of the scalp.
4) Hair Transplants
Hair transplantation is another treatment option for baldness. It is a surgical procedure that is much more invasive and expensive than a topical application of minoxidil .
Modern hair transplants have been able to create natural-looking hair by using follicular units .
There is a slight risk of lichen planopilaris, a type of primary scarring alopecia, after hair transplantation .
On the other hand, hair transplants are a one-time procedure, unlike minoxidil which must be continuously applied to maintain hair growth.
Caffeine was also shown to penetrate the follicles in two minutes when used in a shampoo formulation in humans .
Unlike minoxidil, further studies need to be done to establish the role of caffeine in androgenetic alopecia .
A study with 30 female participants found that adenosine was useful for treating hair loss in women .
7) Low-Level Laser Therapy
Red light (655 nm) laser therapy improves hair density in men with androgenetic alopecia .
A study of 41 participants showed that laser therapy induced hair growth (without side effects) compared to placebo .
Laser therapy is more expensive and invasive than minoxidil foam.
Amla (Phyllanthus emblica L) is a traditional Thai herb that has been used for hundreds of years to treat hair loss in human, much longer than topical minoxidil has existed .
These results suggest that valproic acid therapy may cause hair loss, which may be reversed by biotin. Therefore, biotin is only useful for this type of alopecia, conversely to minoxidil .