DHT Blocking Shampoos: Everything You Need to Know
Reviewed by Kristin Hall, FNP
Written by Grace Gallagher
For many men, shampoo is an afterthought. You choose it because it’s the best value-per-ounce at Costco. Or maybe you had nothing to do with selecting it because your partner bought it and — how convenient — it’s right there in the shower.
But what if your shampoo did more than just smell good and get your hair clean? Well, the best DHT-blocking shampoos do just that by helping you hold onto your hair.
Below, we’ll cover everything you need to know about DHT-blocking shampoos, from the most common DHT-blocking shampoo ingredients (like pumpkin seed oil and saw palmetto) to what hair loss treatments to pair with these hardworking ‘poos for maximum benefits.
What Is a DHT-Blocker Shampoo?
As you may have guessed, DHT blockers, um…block DHT.
So before we get into exactly what a DHT-blocker shampoo is, we need to answer another critical question: What, exactly, is DHT?
DHT is short for dihydrotestosterone, the body’s most potent male steroid hormone. You have DHT to thank for producing male genitalia in fetal development.
During puberty, it’s responsible for body hair, facial hair and a deep voice. But like that small, shy kid who got huge and cocky one summer in middle school, your relationship with DHT can get a little dicey after puberty.
DHT plays a significant role in male pattern baldness (androgenetic alopecia), including hair thinning and a receding hairline because it shortens the hair growth cycle and bonds to receptors in hair follicles, causing shrinking or miniaturization.
DHT-blocking shampoos work at the scalp level. Instead of blocking DHT throughout your body, the ingredients in DHT-blocking shampoos lower DHT activity where it matters most for hair loss — at the hair follicle.
One of the cool things about DHT-blocker shampoos is that many contain natural ingredients like pumpkin seed oil or saw palmetto. These plant-derived substances specifically target hair loss, while other ingredients promote healthy, shiny hair. We’re talking argan oil, jojoba oil, biotin, collagen, keratin, vitamin E, green tea extract and nettle — to name just a few.
But here’s the million-dollar question: Do DHT-blocking shampoos work? Read on to find out what the research says on the best DHT shampoo and discover other ways to help stop hair loss.
Spoiler alert: Yes, they do.
The Best DHT-Blocking Shampoos
Whether you want a hair re-growth shampoo or are looking to reduce hair fallout for healthier-looking hair, the best DHT-blocking shampoos for men can help.
One of the most well-known DHT blockers is the hair loss medication finasteride (known by its brand name Propecia®). It works by inhibiting the enzyme 5 alpha-reductase, which reduces your body’s ability to convert testosterone to DHT.
DHT-blockers are like bouncers — they stop DHT from getting into the hair follicle, where it can stir up trouble.
DHT-blocking shampoos use the same mechanism as finasteride pills. The difference is that they work topically on the scalp, whereas the oral medication works throughout the whole body. This means DHT-blocking shampoos are unlikely to cause the (rare) sexual side effects associated with finasteride.
Read on for what the research says about the best DHT-blocking shampoos.
Saw Palmetto Shampoo
Saw palmetto (or Serenoa repens) is a palm-like shrub that hails from the Southeastern United States.
The ingredient, extracted from the tree’s berries, is buzzy in the hair world — for good reason. It’s gained popularity as a dietary supplement that can help alleviate symptoms linked to an enlarged prostate gland (also known as benign prostatic hyperplasia or BPH).
Our thickening shampoo with saw palmetto is an easy way to incorporate the ingredient into your everyday routine. While more research is needed on saw palmetto and hair loss, initial findings show it’s well-tolerated — and in our opinion, it’s definitely worth a try.
Pumpkin Seed Oil Shampoo
Yeah, they’re good roasted and salted, but pumpkin seeds can also help your hair.
There’s some research supporting pumpkin seed oil for hair growth. A 2014 study found that men who took a 400-milligram pumpkin seed oil supplement daily for 24 weeks showed improvements in hair growth. On average, the supplement seemed to cause a 40 percent increase in hair count in balding men (compared to just 10 percent in the placebo group).
The study was comprehensive, but pumpkin seed oil wasn’t the only ingredient in the supplement, so it’s hard to say for sure that it was the pumpkin doing the work.
The other major issue here? You don’t typically eat your shampoo, and this study didn’t measure the effects of topical pumpkin seed oil — that doesn’t mean we should totally ignore it, though.
While the exact mechanism of how pumpkin seed oil slows hair loss isn’t totally clear, animal studies suggest it may inhibit 5α-reductase, stopping testosterone from becoming DHT.
Remember the hair loss medication finasteride we mentioned? It does the same thing. That’s promising because finasteride can be taken orally or applied topically, suggesting pumpkin seed oil may also work at the topical level.
Ketoconazole isn’t a DHT-blocking medication, but it might be effective for helping hair growth. Ketoconazole is most commonly used to treat fungal infections, including ringworm, athlete’s foot and jock itch — just what you want to slather on your head, right?
Psoriasis and dandruff don’t cause hair loss per se, but all that scratching can damage the hair follicle, leaking to breakage and hair loss over time.
One older study from 1998 compared ketoconazole and the hair loss medication minoxidil (you may know it by its brand name, Rogaine®). Researchers found that 2% ketoconazole shampoo and minoxidil increased the size and proportion of anagen hair follicles at a similar rate.
Imagine a spaghetti maker (or the Play-Doh version if you’re not much of a cook). The smaller the holes in the pasta maker, the thinner the noodles. The same is true of your scalp.
So as your hair follicles shrink, you’re left with angel hair (aka thinning hair) instead of luscious fettuccine. But ketoconazole may increase the diameter of the follicle, so each individual hair is thicker.
With this said, it’s important to note that research into ketoconazole shampoo for hair loss and its effects on scalp DHT levels is still limited.
Our guide to ketoconazole and hair loss goes into more detail about the most recent research on ketoconazole as an active ingredient in hair loss products.
How to Choose the Best DHT-Blocking Shampoo
Wondering what to look for in a hair loss shampoo? Here are some factors to keep in mind when comparing shampoos designed to block DHT and prevent hair loss:
Check the ingredients before you buy. Not all hair loss prevention shampoos contain science-backed active ingredients, so be sure to check the ingredients list before buying anything. Also note that ingredient lists are written in descending order of predominance, so a product contains the most of whichever ingredient is listed first.
See an ambitious claim? Look for evidence. Many shampoo brands make big claims about their products’ abilities to prevent shedding, promote hair growth and add extra volume to your hair — without providing any actual proof. If you see a shampoo that makes big promises, put in some time to research the active ingredients.
Stick with proven, effective ingredients. Almost all ingredients used in hair loss prevention shampoos offer some benefits, whether it’s improved hair texture or just a pleasant scent. However, it’s the active ingredients that do the real work.
Be careful of ingredients that cause irritation. Some ingredients used in shampoos may cause irritation. If you have sensitive skin, look for sulfate-free and paraben-free formulas. Our guide to sulfates in shampoo talks more about the effects of sulfates, as well as steps you can take to avoid them if you have sensitive skin.
When it comes to shampoo for thinning hair, don’t associate cost with effectiveness. Yes, we may have made a joke at Costco’s expense earlier (sorry Costco, we love you and your dollar hot dogs — never change), but many great hair loss shampoos are affordable. When comparing shampoos, look for active ingredients, not a high price tag. Many of the best DHT-blocking shampoos are budget-friendly.
Use a DHT shampoo with hair loss medication. While the right shampoo can help prevent hair loss by itself, you’ll get the best results by combining it with science-based hair loss treatments, such as finasteride and minoxidil. These medications work to block DHT and promote hair growth.
Check customer reviews before you buy. Like other hair care products, DHT-blocker shampoos can vary in quality and effectiveness. If you’re shopping online, read reviews from previous customers before committing to a product.
Don’t forget to use a conditioner. Conditioner helps strengthen your hair and give it extra shine and moisture. Applying conditioner is particularly important if you have a hair type that gets dry or damaged easily. Our Thick Fix conditioner with niacinamide is formulated to support healthy hair growth while helping your hair appear thicker and fuller.
Have realistic expectations. Though many ingredients used in DHT-blocking shampoos are supported by scientific evidence, none should be viewed as alternatives to or replacements for FDA-approved hair loss medications. As such, it’s important to have realistic expectations, especially if you use a DHT-blocker shampoo without medication. While the right shampoo may help stimulate hair growth, it’s unlikely to completely turn around hair loss on its own. It may take a few months before you notice a change, too.
DHT-Blocker Shampoo Side Effects
Good news: DHT-blocker shampoo side effects are usually minimal, especially if you don’t have a sensitive scalp.
Here are some potential DHT-blocking shampoo side effects:
Dryness and itching. Dryness and itching aren’t associated with DHT-blocking shampoos specifically. But if the shampoo contains sulfates (often listed as sodium lauryl sulfate or SLS), you may experience these side effects.
Fading colored hair. Yep, sulfates again. They’re often added to shampoos to get it to foam and lather, but they can be harsh, leading to fading if you have color-treated hair.
Unwanted hair growth. If your DHT-blocking shampoo contains minoxidil as a key ingredient, make sure you’re applying it carefully and as directed. And be on the lookout for unwanted hair growth on other parts of your body.
Skin irritation. DHT shampoos may contain other natural ingredients that may help fight hair loss and increase thickness, like lavender, peppermint, tea tree oil or rosemary oil. While these are generally safe to use for most people, some might experience redness or irritation.
If you had a reaction to a new haircare product before, you’re wise to do a patch test first. Rub a small amount of product onto the back of your forearm and wait to see if a reaction develops.
Hims has helped thousands of men regrow their hair
Hair Growth Treatments to Use With DHT Shampoo
A DHT shampoo certainly deserves a spot in your shower (if you can find one, depending on who you live with). Consider pairing hair loss medications and treatments with your new sudsing routine to tackle hair loss from multiple angles.
We touched on it earlier, so we’ll keep this brief. Finasteride is a prescription medication that stops the conversion of testosterone to DHT (it’s the bounder, remember?)
All men have DHT, but not all men lose their hair. This is because some are more sensitive to the hormone than others. Finasteride can be taken any time of day (as long as you’re consistent from day to day) with or without food.
Minoxidil is a vasodilator, meaning it dilates blood vessels, bringing blood, oxygen and nutrients to the scalp.
It was originally used to treat high blood pressure, but like how potato chips were discovered by accident, minoxidil had a pleasant but unintended side effect of hair growth.
Minoxidil is approved for men and women, whereas finasteride is only FDA-approved for men at this time.
There’s a topical minoxidil foam and a liquid minoxidil solution (both at 5% strength). They work the same way and are applied directly to the scalp. Some people with longer hair think the liquid solution is easier to apply since it has a dropper.
Although rare, some people experience redness and irritation where they apply minoxidil. It’s unclear why this happens, but some researchers think the reaction may be caused by propylene glycol. The foam doesn’t contain this ingredient, so it’s a good choice for sensitive skin or if you’ve tried minoxidil before and had a reaction.
Using Minoxidil and Finasteride Together
These two are the Bert and Ernie of the hair world — they’re super different, but they just jive.
A 2019 meta-analysis looked at the efficacy of minoxidil and finasteride for hair loss. It found that the combo of finasteride and topical minoxidil is more effective and just as safe as using one or the other on its own.
Worried about adding another step to your routine or having more products cluttering up your bathroom? Our topical finasteride & minoxidil spray makes it easy to apply both at the same time.
Other Natural Ingredients
Just as minoxidil and finasteride work well together, you can get similar effects by pairing other natural ingredients.
We mentioned peppermint and lavender oils already. One review shows that rosemary helps regenerate hair follicles in a similar way to minoxidil. So you might look for a shampoo that pairs ingredients that inhibit 5-alpha-reductase (pumpkin seed, saw palmetto and green tea) with rosemary.
Shop by treatment options
No matter the treatment plan, the best place to start is somewhere. Early action is the best hair loss prevention.
The Final Word on DHT-Blocking Shampoo
Here’s a quick recap of what you just read (or skimmed, we get it) on DHT-blocking shampoo for men experiencing hair loss or androgenic alopecia.
When comparing anti-DHT shampoos, look for products that use proven ingredients like saw palmetto or pumpkin seed oil. These substances have been shown to block DHT from getting into the hair follicle.
DHT-blocking shampoos will only work if your hair loss is caused by DHT. If you’re losing hair from stress or a lack of nutrients, try a biotin shampoo or a volumizing shampoo and volumizing conditioner, which can make hair stronger and fuller-looking.
Expensive doesn’t equal better when it comes to hair loss shampoos (and most things, TBH). Before you assume something works well because of its high price tag, check the active ingredients.
If you’re interested in a deeper dive, check out our guide to DHT and male pattern baldness.
Still have questions? Ask a dermatologist what anti-hair loss shampoo is best for your specific situation.
Don’t want to make an in-person appointment? You can also take our hair loss quiz to determine your specific hair loss needs and connect with an online healthcare professional who can help.