Research has revealed that minoxidil, which was initially developed as a blood pressure medication but caused hair growth as a “side effect,” is effective for many patients with hair loss.
Minoxidil is available either as a pill or in a topical formulation, which is applied directly to the scalp. Oral minoxidil has been shown to be effective for both male and female pattern hair loss, as well as several other causes of hair loss. In fact, multiple studies have found at least some hair regrowth in all patients who take oral minoxidil for male pattern hair loss, with around 40% having very significant regrowth of hair. It’s rare for a medication to work for every patient in a study, but this has repeatedly been found for oral minoxidil.
Topical minoxidil is also an option, and is FDA-approved for hair loss. Some people find that the topical form causes itchiness and irritation of the scalp, and may make the hair dry and brittle. Taking it as a pill avoids these issues, and some patients find it to be more convenient.
The dose of minoxidil that’s used for hair loss is far lower than the dose used for high blood pressure, which minimizes the risk. Although any medication can cause side effects, low dose oral minoxidil has shown an impressive safety profile. The most common side effect is excessive hair growth occurring on areas other than the scalp, usually the face. This generally goes away after stopping minoxidil. Other side effects are rare, and fewer than 2% of patients stop taking minoxidil because of them.
A recent New York Times article discussing the research on oral minoxidil has stirred many patients’ interest. We’ve chosen to include low dose oral minoxidil among our offerings, because it’s been shown to be highly effective and also very safe.
Although research is still ongoing to discover all of the effects that minoxidil has on hair follicles, the research that we have so far indicates that it causes hair regrowth in several different ways.
● It opens blood vessels in the scalp, which increases blood flow to the hair follicles.
● It shortens the amount of time that each follicle spends in the resting phase. This gives each hair more time in the growing phase.
● It changes how hormones are processed and act in the scalp, which can have an impact on hair follicles.
As this medication receives more attention from researchers, we may also discover more ways that it causes hair growth.
There are a number of studies examining the efficacy of minoxidil, in both its topical and oral forms. Several studies have found that, in patients receiving oral minoxidil for male pattern hair loss, 100% of them experienced at least some hair growth. In these studies, between 37.5% and 43% of patients show marked improvement.
It should be noted that these are usually younger patients (under age 50), who had mild to moderate hair loss. Not everyone can expect the same results.
Overall, low dose oral minoxidil is a very safe medication, and fewer than 2% of patients stop taking it because of side effects.
The most common side effect is hypertrichosis, or an excessive growth of hair on the face or body. Different studies have had different findings, with anywhere from 15% to 55% of patients experiencing hypertrichosis. Although this side effect seems to be relatively common, it’s usually not severe enough for patients to decide to stop taking the medication because of it. Hypertrichosis is also generally reversible, and will resolve within a few months after a patient stops taking oral minoxidil.
Because minoxidil was initially developed as a blood pressure medication, it’s not surprising that it can also cause side effects related to the cardiovascular system. However, because minoxidil is used at much lower doses for hair loss than for high blood pressure, it’s much less likely to cause these effects. Some patients experience orthostatic hypotension (low blood pressure when changing positions), tachycardia (a rapid heartbeat), and edema (swelling) of the legs, but these occur in fewer than 2% of patients.
Studies looking for a severe effect on the cardiovascular system have generally not found this. In fact, multiple studies have measured patients’ blood pressure for 24 hours after taking minoxidil, and have found no significant changes due to the medication. Even when patients were monitored with a Holter (a wearable device that records electrical signals from the heart), only one patient in a sample of 34 experienced tachycardia.
Patients sometimes experience a temporary increase in hair shedding after starting minoxidil treatment. This will generally only last for about four to six weeks after starting the treatment, although it can last longer for some patients.
A recent meta-analysis published in JAMA Dermatology revealed that oral minoxidil was more effective than topical minoxidil. For those looking to maximize results from minoxidil, the oral formulation is likely to offer more benefit. The topical formulation is available as an over-the- counter option.
In order for minoxidil to work, it has to be converted into an active compound in the body. In many people, this conversion occurs in the scalp. However, in some people, the necessary enzyme to perform the conversion is not found in the scalp, and topical minoxidil won’t be effective for them. However, this enzyme is always found in the liver, so oral minoxidil may work for people who haven’t had success with the topical version.
Topical minoxidil sometimes causes the hair that regrows to have an undesirable texture. It may be dry and brittle, and may tangle easily. Some patients may prefer to use the oral version to avoid this issue.
Some patients find that topical minoxidil causes irritation and itching of the scalp. For these patients, the oral version may be a better option. A study of nine patients who experienced itching with topical minoxidil found that all of them were able to tolerate oral minoxidil, with no side effects besides hypertrichosis.
For dog and cat owners, there’s one other reason to prefer oral minoxidil over the topical version. Both dogs and cats can experience significant toxicity from licking even a small amount of minoxidil, so for those who spend time being physically close to their pets, topical minoxidil may pose a risk. Oral minoxidil avoids this issue.
