The Secret to Longer, Fuller Hair Lies at the Root (2025)

As its name suggests, Crown Affair's scalp serum helps soothe the irritation that develops from dealing with an itchy scalp. Its blend of plumping hyaluronic acid, soothing aloe vera, and anti-fungal tea tree oil minimizes the need to scratch while helping to restore lost moisture and reduce flaking.

• Key ingredients: Hyaluronic acid, aloe vera, and tea tree oil

One satisfied customer writes: "This feels so nice on my dry scalp. Helps stop shedding. Can't wait to see long-term results. Love!!" —klynn1999

Your scalp needs skin barrier protection, just like the face and body. The probiotics in Foreo's formula alleviate dryness and balance excess oil at the same time. It also contains red clover extract to enhance volume over time. "I love this cruelty and fragrance-free serum for its healthy scalp-promoting probiotics, peptides, and anti-inflammatory focus to really support follicle health," dermatologist Brooke Jeffy says.

• Key ingredients: Probiotics, red clover extract, cica

Here's a serum that hits all the marks to ensure a healthy scalp, thanks to its blend of Japanese camellia, brown and green algae, and lavender. Dr. Barbara Sturm's formula is also enhanced with hyaluronic acid to plump, along with purslane extract to help reduce itchiness. And to top off an already impressive ingredient list, it also features a blend of sunflower sprouts and tara extract that work in tandem to protect hair against damage from heat, UV, and pollution. Bridgette Hill, a trichologist and water wellness expert for Culligan, also recommends the brand's Anti-Hair Fall Scalp Serum, which uses many of these same actives to extend the growing phase of the hair follicle.

• Key ingredients: Japanese camellia, brown and green algae, lavender, hyaluronic acid, sunflower sprouts, tara extract

One satisfied customer writes: "I only tried on the scalp serum so far and I have to say I love it. It’s very different to all the other serums I’ve tried before, so definitely a quality product, made my hair feel very smooth and lightweight and soft I really like it!" —Asma

One reason your hair may not grow as quickly as it should is likely due to clogged hair follicles. This pick from Vegamour uses exfoliating vegan silk protein and willowherb to help clear the way to health by freeing your follicles of product buildup or lingering dead skin cells. And once buildup is gone, the fortifying actives in your treatments and conditioners can penetrate both the hair and scalp more thoroughly.

• Key ingredients: Vegan silk protein, zinc PCA, willowherb, baobab oil, and marula oil

One satisfied customer writes: "I have an oily scalp and have been on a recent mission to correct that. This product is life-changing. I’m 42 years old and have always had to wash my hair daily in order for it to look good. Since I’ve started using this product, I have been able to go for several days now without having to wash my hair. I get so many compliments and have been telling everyone about it!" —Rachel M.

Similar to the build-up-clearing powers of Vegamour's treatment, this one from Bread Beauty Supply uses alpha hydroxy acids (AHAs) to keep your scalp in the free and clear. Mandelic acid and gluconolactone gently reboot the scalp without irritation thanks to the formula's addition of soothing eucalyptol, which also nicely adds a layer of antioxidant protection.

• Key ingredients: Mandelic acid, gluconolactone, chinaberry extract, eucalyptol

One satisfied customer writes: "It soothes irritation, hydrates deeply, and leaves my scalp feeling refreshed without any greasy residue. My curls are thriving with added shine and health. A must-have in any hair care routine!" — nukirowson

Aveda's top-rated scalp serum helps hair look full and lifted instantly and over time, making it especially ideal for fine and thinning hair. It uses a three-pronged approach that neutralizes and eliminates oxidative stressors, strengthens follicles from the inside out, and rejuvenates the scalp.

• Key ingredients: Eclipta, Alpinia, and ginger

One satisfied customer writes: "The Aveda Invati Ultra Advanced Revitalizing Scalp Serum has completely transformed my scalp care routine! From the first application, I noticed how soothing and refreshing it feels. The lightweight formula absorbs quickly without leaving any greasy residue, and it has significantly improved the overall health of my scalp." —Katya_knopa

Jeffy also recommends this fragrance-free pick for sensitive scalps. Squalane plays a key role in its formula to minimize uncomfortable dryness that may cause further scalp irritation without the addition of silicones or sulfates. It's so gentle that the dermatologist-developed serum has even received the National Eczema Association's seal of approval.

• Key ingredients: Propanediol caprylate, sarcosine, bisabolol, ethylhexyl olivate, and squalane

One satisfied customer writes: "This is the only thing that helped stop my long-term dandruff problem. I’m on my second bottle. My hair is soft. My scalp is healthy. I am happy thank you so much!" —Casey K.

We're fans of just about everything Queen B creates, including these hair growth drops from her beauty brand Cécred. Though ideal for fortifying the entire scalp, the drops are especially effective around your hairline. Using a blend of peptides, keratin, and biotin, the formula doesn't just make hair look fuller but actually increases the density of your hair strands with each use.

• Key ingredients: Biopeptide-5, bioactive keratin ferment, fermented rice powder, biotin, rose extract, ginger extract

One satisfied customer writes: "I love consistency and I'm already starting to see results! I have locs and I was starting to notice that, the ones on my edges were starting to thin. I can honestly say that since I've started using the drops I am already noticing baby hairs coming in! I absolutely recommend buying the drops." —Kisha H.

This water-based serum absorbs quickly and aims to increase hair density after eight weeks of daily use. It also contains over 21 different actives to support hair growth and scalp health while enhancing hydration.

• Key ingredients: Biotin, aloe vera stem cell extract, rosemary extract

One satisfied customer writes: "I have had a lot of hair all my life, but after my pregnancy and a hormonal problem, my hair fell out a lot and I started to get gaps, especially in the forehead area. I have been using the product for four weeks and it has worked wonders for me." —EmmaAydogan

Powered by the same technology used in their viral skincare staples, Augustinus Bader's The Scalp Treatment targets the weak spots within each of your hair follicles and replenishes them with strengthening and stimulating peptides, lipids, and minerals to strengthen your hair. With regular use, you'll notice less shedding, breakage, and scalp dryness overall.

• Key ingredients: Vitamin B5, minerals

One satisfied customer writes: "I love, love, love this serum! I can actually see little baby hairs filling in my thinning hair! Before starting to use this serum you could actually see fairly far up on my scalp in between my hair. But no more!" — JSchmiett

For a more general approach to scalp care, Hill recommends adding this pre-shampoo scalp serum to your rotation to set the stage for hair strength and growth. The all-in-one favorite cleanses the scalp, restores its microbiome, and encourages cellular turnover.

• Key ingredients: Castor oil, orange essential oil, and lavender essential oil

One satisfied customer writes: "I absolutely love this scalp oil. I've used many scalp scrubs before, never thought an oil would help alleviate an oily and irritated scalp but this one is incredible. My scalp feels incredibly clean after the wash." —Sorana

Jeffy adds that scalp serums can help hydrate the scalp and support an environment that's conducive to hair growth. "Our hair follicles are finicky, and we want them to be living in the most supportive scalp environment possible so they work as effectively as possible." More specifically, scalp serums are often laced with concentrated ingredients that can deeply moisturize both the scalp and hair, reduce dandruff, and stop hair loss or encourage hair growth.

Hill notes that the hardness of the water you're washing with can negatively impact your scalp. "Without proper mitigation, hard water causes mineral build-up on the scalp, which can weaken roots, strip the scalp of natural oils, and impact the efficacy of the products you use on your hair," the expert advises.

• Brooke Jeffy, MD, is a board-certified dermatologist in Scottsdale and the founder of skincare brand BTWN .
• Dr. Jodi LoGerfo is a board-certified dermatologist at Orentreich Medical Group in New York.
• Bridgette Hill is a certified trichologist and water wellness expert for Culligan.

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