Key learning points
- Minoxidil has been approved by the FDA for the treatment of hair loss since 1988.
- Some dermatologists now prescribe oral minoxidil in low doses to combat thinning hair.
- Oral minoxidil may have fewer side effects and provide the same results.
If we are to believe shampoo commercials, all it takes for thick, shiny hair is a bottle of soapy water. But for thousands with hair loss, it is difficult to regrow thinning hair.
Now dermatologists are rediscovering an existing treatment – minoxidil – and prescribing it in a different form. A growing number of doctors, after years of trial and error, have started prescribing low doses of oral minoxidil instead of topical minoxidil, and a scientific review points to its efficacy.
A review from 2020 published in the International Journal of Dermatology found that between 61% and 100% of patients with androgenetic alopecia saw significant improvement with a low dose between 0.25 mg and 0.5 mg of oral minoxidil. The report indicated that some of the success may be linked to greater patient compliance, as the oral method lacks the mess and potentially irritating side effects that can occur with topical use.
What is minoxidil?
Minoxidil was originally developed as a blood pressure medication and was used to combat hypertension. The medication was effective, but produced a curious side effect: hypertrichosis or extra hair growth. Unfortunately, at the originally prescribed dosage, that hair growth could occur all over the body, altering the hair’s color, texture and thickness.
After observing the stimulated hair growth, doctors experimented with using the drug topically so patients could determine where they were trying to regrow hair. Minoxidil was approved topically for the treatment of hair loss by the Food and Drug Administration (FDA) in 1988 and became the active ingredient in products such as Rogaine and eventually became available over the counter.
Minoxidil is still prescribed for hypertension, but in much higher doses than used for hair growth.
How Minoxidil Starts Hair Growth
Minoxidil stimulates hair growth by pushing hair follicles into their anagen phase, according to Geeta Yadav, MD, board-certified dermatologist and founder of FACET Dermatology.
“Anagen is the growth phase of the hair follicles,” Yadav told Verywell. “Catagen is the stable phase and telogen is the excretory phase. Minoxidil indefinitely shifts the follicles into the anagen phase.”
When patients first start taking minoxidil, they may start to notice more loss, Yadav said. In the first two months of use, users may see more shedding as the follicle has to go through the entire cycle before the follicles can return to the anagen growth phase.
Once in anagen, it can still take months to see results depending on the rate of hair growth.
Yadav said that with an average growth of one centimeter per month, it would take at least six months to see much progress, and if the patient stops taking the medication, all progress will be lost within a few months.
“Minoxidil is not a drug. It has good efficacy, it’s the primary care standard, but it’s a commitment,” Yadav said.
Why the push for a pill?
If topical minoxidil works, why the sudden interest in oral treatments? While oral use has been making headlines lately, doctors have been investigating its use for quite some time now, with notable studies confirming its efficacy dating back to 2019.
While oral minoxidil for alopecia is not FDA-approved, the preponderance of evidence encourages many doctors to experiment off-label with pills in dosages that work for their patients.
What is off-label use?
Yadav said that while minoxidil topical has great efficacy, it is not the most convenient to use. Minoxidil is generally prescribed in a 2% or 5% formulation to be applied to the scalp daily. Some patients get tired of the mess or find they have a skin sensitivity to the foam, making it irritating to apply. Some patients have also reported that hair texture can change and become dry and prone to breakage.
“The oral formulation is sometimes just a little simpler and easier to take,” Yadav said. “If you can dose it right, you generally see mild side effects; it is effective and well tolerated.”
That dose is very low. According to the International Society of Hair Restoration Society (ISHRS), dermatologists prescribe daily doses of less than 5 milligrams (mg) in combination with spironolactone, another antihypertensive drug commonly prescribed to treat acne and androgenic alopecia.
In addition to being easy to use, oral minoxidil is also cost effective. A quick search shows that even without insurance, a bottle of 30 pills of minoxidil 2.5mg is less than $5.
For some, topical treatment remains the best choice
While oral minoxidil has been making headlines recently, it isn’t necessarily the first choice of many dermatologists. Jeannette Graf, MD, assistant clinical professor of dermatology at the Mount Sinai School of Medicine, told Verywell via email that she would probably first prescribe minoxidil as a topical.
Graf was in medical school when the discovery of its hair-growth properties was first discovered, and remembers the subsequent discontinuation of minoxidil oral due to extreme hair growth in women in unexpected places.
“Hair loss in women starts at the temples. Depending on the degree of severity, it covers the entire top of the scalp, including the frontal and parietal areas,” Graf said. While there are many good doctors who use higher doses in women, I tend to stay at 5% because I have seen hypertrichosis at higher doses.
Graf said that while she has found success with topical minoxidil, she often prescribes it in combination with other medications in an effort to reduce skin irritation.
How to find the right formula?
Although topical minoxidil is now available over the counter, oral minoxidil is available by prescription only. Those already undergoing treatment for hair loss can consult their dermatologist for a prescription for minoxidil for off-label use.
Graf and Yadav agree that before trying any hair growth cure, it’s important to determine the cause behind hair loss. Hormonal changes can have a major impact, especially for women.
“Women experiencing hair loss should first undergo medical treatment to rule out possible medical problems that could be contributing factors, such as thyroid, autoimmune disease, hormonal issues, etc,” Graf said.
Those contributing factors may mean that different treatments are more effective. Yadav said there are more than 10 different types of alopecia, which are grouped as alopecia with or without scars. Even in men and women with male or female pattern baldness, also known as androgenic alopecia, there is a point where even minoxidil may not help.
“Androgenetic alopecia, which treats Rogaine or minoxidil, is a scarless alopecia, but the follicles are miniaturized,” Yadav said. “The longer that follicle is miniaturized, the less likely you’ll be able to stimulate hair growth. It’s possible, but it’s less likely.”
Depending on the cause of hair loss, several treatments are available, including platelet-rich plasma given by injection and oral medications such as spironolactone and dutasteride. Effective drugs can also vary from man to woman.
What this means for you?
Minoxidil has been an effective hair loss treatment for decades, but it can be messy and irritating to apply topically. Taken orally and in very low doses, minoxidil can be effective, cost-effective, and convenient, but requires a doctor’s prescription. Talk to your dermatologist about whether oral minoxidil is the right treatment for your thinning hair.