Ketoconazole shampoos have become an increasingly popular way to treat hair loss. This is in spite of the fact that the makers of these shampoos do not officially sell them for hair loss.
Why is this, and is a ketoconazole shampoo something you should consider adding to your hair care routine?
This in-depth guide will give you the answer to all these questions.
What Is Ketoconazole?
Ketoconazole was discovered in 1976 by Janssen Pharmaceutica in Belgium (1). It belongs to a class of antifungal medications called imidazoles. It came on the market in the early 1980s.
Today you can find it under several brand names, including Extina, Xolegel, and Ketoderm. However, the most popular brand name is Nizoral. This is one of the most common anti-dandruff medications on the market today.
This article will look primarily at the shampoo version, but ketoconazole is available in many forms. These include gel, foam, cream, and even oral tablets.
How It Works
Ketoconazole is an antifungal, meaning it kills fungi and yeasts. The drug stops the production of an organic molecule commonly found in fungus and yeast: ergosterol (2). This interferes with the cell membrane of both organisms. With the cell membranes compromised, the organisms are no longer able to reproduce.
Ketoconazole is a “broad spectrum” drug (3). This means it is effective against many species of micro-organisms. These include not only the fungus responsible for most cases of dandruff (discussed below) but many other, often more severe, fungal infections of the scalp.
Among other conditions, ketoconazole can also treat thrush, psoriasis and tinea capitis.
Is Ketoconazole a Hair Loss Treatment?
It is important to stress at the outset that ketoconazole is sold as an over-the-counter medicated shampoo for the treatment of dandruff and certain fungal infections. Depending on its form (topical or oral) ketoconazole can be used to treat fungal infections in most parts of the body.
Male pattern hair loss is not a fungal condition. So neither the manufacturer markets Nizoral shampoo as a treatment for pattern hair loss nor has the FDA approved it for this indication.
Having said that, in recent years ketoconazole shampoos have gained somewhat of a following among the hair loss community. Supporters of ketoconazole often reference some research studies conducted a few years ago. The authors of those studies looked at ketoconazole shampoos outside of their intended use, and in particular as a treatment against male pattern baldness.
Before we get to that, let’s have a look at ketoconazole’s intended uses.
Ketoconazole, Dandruff, and Seborrheic Dermatitis
All healthy people lose skin cells on their scalp and the rest of their body all the time, but these are normally not visible. In dandruff, this changes.
The white, ugly, crusty flakes seen in dandruff are actually a cluster of dead skin cells that for one reason or another retained a high degree of cohesion and detached as one piece from the scalp.
Scientists today believe this condition is multifactorial. In other words, it can have many causes, including airborne chemicals and even stress. But in most cases, the chief culprit is a fungus by the name of Malassezia. This is a family of fungi normally found in the scalp of healthy people. But in dandruff, Malassezia multiplies out of control and more or less takes over the scalp.
The exact mechanism by which Malassezia causes dandruff is not clear. Be that as it may, the evidence implicating Malassezia in the pathogenesis of dandruff is strong. For example, a 2014 study found Malassezzia to be present in the scalp of 84% of a sample of dandruff patients (5). This was in contrast to healthy people, where Malassezia was only found in 30%.
With a powerful anti-fungal like ketoconazole, the yeast is no longer able to reproduce or survive. This leads to less scaling and reduction of the other bothersome symptoms, like itching and redness.
Like dandruff, the main symptoms of SD are inflammation, itching, scaling, redness, flaking (yellowish or white), and overproduction of grease. Unlike dandruff, it can also occur in areas outside the scalp. These include the ears, eyelids, neck, upper back, chest, and armpits.
While scientists have not identified the exact cause of SD, they believe a number of factors regulate the severity of this condition. These include age, gender, and immune system health. As with dandruff, Malassezia also plays a role.
Unsurprisingly, given what has been discussed so far, SD often responds very well to treatment with ketoconazole (8). When the SD affects the scalp the shampoo version can be used, but for SD of the face or other areas of the body, the cream is applied.
What About Ketoconazole and Hair Loss?
As mentioned above, ketoconazole is not licensed or sold as an anti-hair loss drug, but some balding men do use it for this purpose.
A 2005 Japanese study was one of the first to directly study ketoconazole’s role in hair growth (9). The research was on mice, and the results were quite promising.
A similar study was performed in 2014 – again on mice – but this time it compared ketoconazole to minoxidil and minoxidil with tretinoin (an acne treatment) (10).
The mice were first split into four groups (of five mice), and their dorsal hairs were shaved. A stain was then applied so researchers could better track the growth of new, non-dyed hairs.
The mice were split into four groups as follows:
- I was the control, and it received 1 mL of 95% ethanol once daily for 6 days/week for 3 weeks.
- II received Ketoconazole solution 2%, 0.1 mL once daily for 3 weeks.
- III received Minoxidil solution 5%, 0.1 mL once daily for 3 weeks.
- IV received equal amounts of Minoxidil solution 5% + Tretinoin 0.1%, 0.1 mL once daily for 3 weeks.
After three weeks, it was obvious that ketoconazole, minoxidil, and minoxidil with tretinoin were all superior to the placebo group. This was in terms of both number as well as diameter of the hair follicles.
These differences were easily visible to the naked eye, as you can see in the side-by-side comparison image below.
On the left is the control group, showing insignificant growth (as noted by the presence of dye). On the right is the ketoconazole treatment group, with significant growth in just three weeks’ time.
Ketoconazole And DHT
As noted by the researchers, the positive effects of ketoconazole likely “stem from its antiandrogenic properties.”
When it comes to battling male pattern baldness (or androgenetic alopecia – AGA) one of the best ways to do so is to target and remove DHT from the scalp. DHT (dihydrotestosterone) is one of the four androgens or male hormones. It is also the primary molecule implicated in male pattern baldness (11).
This is because those with AGA are sensitive to DHT, and this can cause miniaturization of the hair follicle. As the follicle miniaturizes, the hair growth cycle is altered, and eventually, the hair shaft completely stops growing.
Medications like finasteride work by blocking DHT all over the body (12). However, blocking DHT in the scalp is equally as effective, and because it is more selective, leads to far fewer side effects.
It turns out ketoconazole may also play a role in inhibiting the synthesis of DHT when applied directly on the scalp (13). Studies with prostate cancer patients have also confirmed the potent antiandrogenic properties of ketoconazole (14).
Research With Balding Men
One of the first studies on the topic was published more than 20 years ago (15).
The study recruited 39 men with androgenetic alopecia, of which 27 used Nizoral shampoo for a 21-month period. The other 12 men used regular unmedicated shampoo.
At the end of 21 months, the men in the Nizoral group showed improvements in the proportion of anagen hairs (i.e. hairs in the growth phase of their cycle) as well as in the average diameter of their hair shaft.
This combination of more growing hairs that were also thicker led to fuller hair after 6 months of the treatment. The gains continued until they stabilized after 15 months. The men who were using the unmedicated shampoo, on the other hand, continued on the slow but steady decline that is typical of AGA.
The results of this first study spurred the researchers to conduct a second study (both of these studies were reported in the same paper).
In this second study, two groups of men were studied. There were four men in each group. One group used Nizoral shampoo, and the other group applied daily topical minoxidil (while also using regular, unmedicated shampoo).
After six months, both groups of men showed an increase in hair density which was 18% in the ketoconazole group and 11% in the minoxidil group. The median hair shaft diameter in both groups increased by 7%.
The authors concluded that ketoconazole shampoo results in an unequivocal increase in hair density, size, and proportion of anagen hairs.
There have been more recent studies on the topic, including those performed in 2002, 2006, and 2011 (16).
While each of these studies did see hair growth in most of its subjects, there were some limitations. These include sample size and consistency of use among test subjects.
Female Hair Loss
In 2019, a pair of researchers from Egypt studied topical ketoconazole as a treatment for female pattern hair loss (female AGA). The researchers recruited 40 women with hair loss into two groups (17). The first group received 2% topical minoxidil. Minoxidil is a tried and tested, FDA-approved treatment for this condition. The second group received a 2% topical ketoconazole solution. The women in both groups applied the treatment daily for 6 months.
While women in the minoxidil group saw the first signs of regrowth earlier, by the 6-month mark both groups of women had statistically significant regrowth. Ketoconazole treatment also resulted in fewer side effects. Overall, women in both groups were equally happy with their treatment. The results of this study suggest that topical ketoconazole can be an effective treatment option for women with hair loss.
Cost and Availability
You can purchase ketoconazole shampoos in two strengths: 1% and 2%. In many countries, the 1% strength is sold over the counter, while the 2% is available by prescription only.
As a popular over-the-counter fungal treatment, there are a number of brands to choose from. The most common brand is Nizoral, and you can purchase an 8-oz bottle for around $15.
While this is a bit pricey, you only have to use the product a few times per week at the beginning of treatment. This means that the product will last a reasonable length of time.
As with any medication, ketoconazole has a few possible side effects that may interfere with its continued use or make continuation altogether impossible.
Shampoos that contain ketoconazole are relatively safe, at least for short-term use as intended.
According to the Mayo Clinic, the most common of these are itching, stinging, burning, or irritation (17). On rare occasions, ketoconazole-containing shampoo may cause hair loss.
In the event side effects occur, they may subside as your body adjusts to the medication. If you find these side effects are too strong and cause distress, discontinue treatment and consult with your doctor.
As with any medicated product, it is a good idea to consult with your physician prior to usage anyway. This is especially true if you are currently on any prescription medications, or if you have any chronic health conditions.
While ketoconazole is a relatively safe topical drug, this is not the case with oral use.
In 2013 the FDA issued a warning and limited the usage of ketoconazole tablets (18). The FDA warned of potentially fatal liver problems and serious adrenal gland problems. The agency also warned of potentially very serious drug interactions.
The manufacturers had to change the label of the drug, and the FDA recommended the drug no longer be a first-line treatment for fungal infections. To be clear, these warnings apply to the oral version of the drug only, not the shampoo.
Adding Ketoconazole to Your Hair Care Routine
As readily available shampoos, ketoconazole products are something you can easily add to your regular hair care routine.
Since this is a medicated product, you should follow a consistent regimen for six to eight weeks. This means using the shampoo every two to four days for the mentioned length of time, and then using it periodically ( one to two times per month) for continued benefits.
How to Use Ketoconazole Shampoo
If you decide to use ketoconazole, you will want to ensure you are using it most effectively. Here is a closer look at the instructions:
- Wet the area of the scalp affected by hair loss.
- Apply the ketoconazole shampoo directly to the area affected by hair loss, and a large radius around it.
- Massage the shampoo into the affected area for one minute, allowing it to fully lather.
- Let sit for 5 minutes.
- Rinse with lukewarm/cool water.
Practically, it will be much easier if you start your shower by applying ketoconazole. You can then wash the rest of your body while you let the ketoconazole act on your hair.
While you can apply ketoconazole shampoo to the entire scalp, pay particular attention to the area of hair loss. This means focusing the majority of your massaging efforts there, and using a circular motion while doing so.
By allowing it to sit, you also ensure the ingredients penetrate the scalp and hair follicles.
But you may be wondering:
“Why must I rinse with lukewarm/cool water?”
The fact is, hot water causes damage to the scalp and hair follicles. It leads to dryness, inflammation, and irritation and you should avoid it as much as possible.
By rinsing your scalp with lukewarm/cool water, you prevent any irritation from occurring.
Coldwater rinses have other benefits, too! Namely, increased circulation which is great for oxygen/nutrient delivery and waste removal.
A Word of Caution
While ketoconazole shampoos may play a role against pattern hair loss, this beneficial effect comes at a price. Because Nizoral and other ketoconazole shampoos are medicated products intended for short-term use, they are very harsh on the hair shaft. Frequent use of ketoconazole shampoo will likely leave your hair dry, brittle, and prone to breakage. Depending on how frequently you cut your hair and how long it is, this might be visible to the naked eye.
If you have long hair, you will probably also find that ketoconazole shampoo makes your hair tangle far more than usual. For this reason, you will probably have to use another shampoo after Nizoral, as well as a conditioner.
There is no doubt that ketoconazole can help significantly in the treatment of SD and dandruff. The jury is still out on its hair-growth properties, though there is some compelling evidence in this regard.
This does not mean, however, that ketoconazole on its own will be able to reverse your hair loss and restore a full head of hair. In the event it does work for you, it will most likely stabilize your hair loss. If you do see some hair growth, this will generally be mild.
The main drawback to ketoconazole shampoo is that it is a medicated product, which is not intended for long-term, frequent use. For this reason, if you add it to your hair loss regimen, aim to use it as infrequently as possible. Because ketoconazole is harsh on the hair, you will probably have to use it in conjunction with another shampoo.