Medically reviewed by Vicky Davis, FNP
Written by Our Editorial Team
Last updated 8/15/2021
Search for hair loss shampoos online and you’ll find hundreds of different products, from natural treatments that offer thicker, fuller hair to clinical shampoos designed to block DHT and prevent hair loss.
You’ll also find a lot of promises -- of certain ingredients eliminating hair loss, regrowing lost hair and giving you back the hairline you used to have.
Just like most personal care products, some men’s hair loss shampoos offer real benefits, while others are designed with promotion and marketing in mind more than measurable hair regrowth or hair loss prevention.
In this guide, we’ll look at the key ingredients that you’ll want to look for in a shampoo to prevent or stop hair loss.
We’ll also review several studies that demonstrate which ingredients could potentially play a role in stopping hair loss and helping you grow a thick, healthy head of hair.
While there’s no need to look for all of these ingredients in a hair thickening shampoo, you may want to try a shampoo that contains at least one or two or the active ingredients featured on our list.
First of all, let’s answer a common question: Do hair loss shampoos and other over-the-counter products actually work?
Since the active ingredients for hair growth used in shampoos can vary so dramatically, there’s no simple “yes” or “no” answer to this question.
However, research does show that some ingredients used in hair loss shampoos appear to cut down on hair shedding and improve hair growth.
For example, there’s real scientific research showing that the ingredients ketoconazole and saw palmetto can produce improvements in hair growth and lower the severity of pattern hair loss, or androgenetic alopecia.
We’ve discussed this research in more detail below, as well as how it relates to your hair growth and general hair health.
As such, it’s best to think of these ingredients as “maybes” when it comes to treating hair loss.
Put simply, while there isn’t that much research available on the effects of shampoo on hair loss, studies have shown that certain ingredients offer benefits when used topically.
Since shampoo is a convenient, practical way of applying these ingredients to your scalp, using a hair loss shampoo is a good option for accessing their potential benefits.
Ready to begin? Let’s get started by looking at the most important ingredients you should look for in a men’s hair loss shampoo: DHT blockers.
We’ve talked about the science behind this hormone in more detail in our guide to DHT and its role in male pattern baldness.
These ingredients work by shielding your hair follicles from the effects of DHT, which may limit damage and prevent hair loss.
Ketoconazole is one of the most common active ingredients in hair loss shampoos. Designed to control fungal growth and treat fungal skin infections, ketoconazole is widely used in shampoos and pharmaceuticals as a means of controlling dandruff, skin rashes and hair loss.
One of the biggest benefits of ketoconazole is that it’s linked to disruption of the DHT pathway -- a process by which testosterone is converted into DHT, the hormone that actively attacks frontal and crown hair follicles in men.
Research published in the journal Dermatology has found that ketoconazole shampoo improves the size and proportion of anagen (growth) hair follicles.
While the link between ketoconazole and DHT isn’t as strong as it is for anti-hair loss drugs like finasteride, it’s still a good sign that ketoconazole actively works on the same receptors that are responsible for male pattern baldness.
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Salicylic acid is a naturally occurring substance that’s found in everything from walnuts to white willow bark. It’s a common active ingredient in acne treatments, but is also known for its effects on hair loss.
As an exfoliant, salicylic acid is used to wash away excess sebum -- the oil-like substance that’s secreted by the sebaceous glands in your scalp.
In the scalp, sebum can contain large amounts of dihydrotestosterone, the hormone responsible for male pattern baldness.
Salicylic acid doesn’t directly block DHT at the source (like finasteride) or disrupt DHT pathways locally (like ketoconazole), but its role in reducing sebum levels makes it a great tool for keeping excess DHT at bay.
Thanks to its antifungal effects, it’s also a helpful preventative treatment for scalp ringworm and other scalp conditions, such as seborrheic dermatitis.
Pyrithione zinc is a coordination complex of zinc that inhibits the division of fungal and bacterial cells, making it an important ingredient in treating dandruff and seborrhoeic dermatitis.
Although research on pyrithione zinc for hair loss is limited, some studies have found that it may offer benefits for preventing hair loss and stimulating hair growth.
They also looked at the effects of pyrithione zinc and minoxidil when used together
They found that the pyrithione zinc shampoo produced a mild increase in hair count in men with moderate androgenetic alopecia.
However, the minoxidil solution was significantly more effective, with men in the minoxidil group growing more than twice as much new hair over the course of the 26-week study period.
Although the effect of pyrithione zinc on hair loss appears to be modest, its anti-dandruff effects still make it an ingredient worth considering.
Saw palmetto extract is a natural extract of the saw palmetto fruit -- a subtropical fruit that grows in the Southeastern United States.
Several studies have looked at the effects of saw palmetto on DHT, the androgen hormone that causes male pattern baldness.
In one study, researchers compared DHT levels in the prostate -- a part of the body that’s often affected by DHT.
They found that levels of DHT in the prostate decreased by 32 percent in men who used a supplement containing a saw palmetto herbal blend.
Other research has looked more directly at the effects of saw palmetto on hair health. In a 2012 study published in the International Journal of Immunopathology and Pharmacology, a group of researchers compared a saw palmetto supplement with the hair loss medication finasteride.
Over the course of 24 months, 38 percent of the men that used the saw palmetto treatment saw an increase in hair growth.
In comparison, 68 percent of the men treated with finasteride noted improvements.
It’s important to note that research on saw palmetto is still quite limited, with the few studies that are available generally small in size.
We’ve talked more about the current research on saw palmetto for hair loss, its findings, and its limitations in our guide to saw palmetto as a treatment for hair loss.
Treating male pattern baldness is a two-step process. The first step is preventing hair loss from getting worse. The second is stimulating new, sustainable hair growth.
While the ingredients listed above appear to offer benefits for step one, none appear to have a measurable effect on the speed and thickness at which your hair grows.
Below, we’ve listed several growth-promoting active ingredients that you’ll want to look for when you compare men’s shampoos for hair loss.
It’s worth pointing out that biotin is a water-soluble vitamin and that there’s currently no scientific evidence that your body can absorb it through the scalp.
As such, you’ll likely get better results from a biotin supplement than you would from a shampoo that contains biotin.
You can also get biotin through your diet. Foods such as eggs, salmon, pork, minced beef, tuna, beef liver, almonds and spinach are all rich sources of biotin, making them worth adding to your diet if you’re aiming to maximize your hair growth.
Niacin, also known as vitamin B3, is another vitamin that you can find in a lot of men’s hair loss shampoos.
Research shows that niacin and its derivatives can stimulate hair growth when applied to areas of the scalp with hair loss. It’s worth noting that this study featured female participants, rather than men with male pattern baldness.
Nicotinamide, a water-soluble amide form of niacin, also has anti-inflammatory effects that may help to prevent skin irritation.
Since niacin doesn’t block DHT, it won’t protect your hairline or reduce thinning on the crown of your head.
However, it may contribute to healthy hair growth and improve your hair’s thickness, density and general appearance.
Pumpkin seed oil is another naturally occurring substance that has shown a measurable effect on hair thickness, growth rate and quality in research.
In one study, researchers found that men with male pattern baldness who took a pumpkin seed oil supplement showed a 40 percent improvement in hair count after 24 weeks of treatment.
In comparison, men who used a placebo only showed a 10 percent increase in growth.
Other research has found that phytosterols, a type of natural plant compounds, in pumpkin seed oil may inhibit 5-alpha-reductase.
Just like with saw palmetto, biotin and other ingredients, it’s important to note that most scientific research into the effects of pumpkin seed oil focuses on oral consumption.
Right now, there isn’t any data showing that topical application of pumpkin seed oil, such as in a shampoo or moisturizer, has any effect on hair growth in humans.
Because pumpkin seed oil is widely used in hair loss shampoos, it’s not a challenging ingredient to find.
Most of the time, you can find it used as one of several oils in hair loss shampoos, often alongside the ingredient listed below.
Rosemary oil is another oil that may show some benefits for hair growth in a few small scientific studies.
In fact, in one study, researchers found that rosemary oil was equally as effective at promoting hair growth as minoxidil, an FDA-approved hair loss medication.
Interestingly, this study found that rosemary oil was less likely to produce many of the negative side effects associated with minoxidil, such as an itchy scalp.
Like pumpkin seed oil, rosemary oil is a common ingredient in hair loss shampoos. It’s also easy to find as an essential oil, making it a simple addition to any shampoo formula if you’re aiming to fight hair loss from every angle.
Because many of the ingredients used in hair loss shampoos are quite new, not all of them have been studied by scientists and researchers.
This means that you’ll find a lot of speculation online about certain ingredients, particularly those that have only been used in shampoos for a few years.
Below, we’ve listed several of the most common new active ingredients that you can find in hair loss shampoos, along with their purported benefits.
While these ingredients aren’t proven to have an effect on hair loss, many offer other health and skin benefits that make them worth looking for anyway:
Green tea extract is thought to have a positive effect on hair growth, with a 2007 study from South Korea showing an increase in growth of hair follicles.
Cysteine is a popular ingredient in hair loss shampoos that has some links to anti-aging effects, although little scientific research is available on its effects for hair growth.
Panthenol is another popular ingredient in hair loss shampoos, as it’s believed to have benefits for hair thickness and moisturization.
Inositol is a vitamin-like substance with some benefits for hair and skin health, but isn’t proven to have an effect on hair growth or preventing hair loss.
Horsetail extract is another natural substance that’s commonly used in men’s hair loss shampoos, although it’s only been studied as part of a blend of hair loss ingredients.
Some of the above ingredients can be found far down the list of ingredients on many hair loss shampoos, usually in trace amounts.
While these ingredients might have positive effects on hair growth, it’s best to think of them as secondary to the DHT blockers and hair growth agents listed above.
A good quality shampoo can prevent damaged hair, keep your scalp healthy and produce the environment your hair needs for healthy growth.
If you’re aiming to stop hair loss, you’ll likely get the best results by combining FDA-approved hair loss treatments like minoxidil and finasteride with a growth-promoting shampoo, a healthy diet and good hair care habits.
Our Hair Thickening Shampoo contains saw palmetto, one of the natural ingredients featured above, to target DHT while promoting volume and moisture.