Rated 4.8 Excellent 50,312+ Reviews
Dr. Groot Hair Thickening Roll On Serum
- 💜 Roll-on precision applicator
- 🧴 Skincare ingredients for your scalp
- 🌿 Biotin, rosemary & niacinamide
- 💧 Non-greasy, lightweight serum
- ✅ Dermatologically tested formula
$24.99
$49.99
SPRING SALE - SAVE
$25.00
WARNING: Low Stock Notice
This product sold out 12 times last year. We encourage you to take advantage of the limited sale and buy now. Subscribing protects you against future stockouts. PS: Only available here, don't buy fakes on Amazon/eBay
Becky K
Ever since I started rolling this into my edges every night, the little hairs I thought were gone for good have been slowly making their way back.
Dr. Groot Hair Thickening Roll On Serum
Your Hair Isn't Thinning Because Of Bad Luck
Most thinning hair products treat the strands, not the source — but this roll-on serum targets the scalp directly with biotin, rosemary, niacinamide, and salicylic acid, essentially bringing skincare-level ingredients to the place where hair actually grows. The lightweight, non-greasy formula absorbs completely so you can apply it before bed and wake up without an oily mess — just consistent, targeted scalp support night after night. Women using it on their edges, part lines, and thinning crown areas have noticed their hair looking noticeably fuller in as little as a few weeks of daily use.
10,000+ Happy Customers
+
3rd Party Lab Tested
+
30 Day Money Back Grantee
+
10,000+ Happy Customers
+
3rd Party Lab Tested
+
30 Day Money Back Grantee
+
10,000+ Happy Customers
+
3rd Party Lab Tested
+
30 Day Money Back Grantee
+
10,000+ Happy Customers
+
3rd Party Lab Tested
+
30 Day Money Back Grantee
+
10,000+ Happy Customers
+
3rd Party Lab Tested
+
30 Day Money Back Grantee
+
10,000+ Happy Customers
+
3rd Party Lab Tested
+
30 Day Money Back Grantee
+
Clinically Studied
Clinically Studied
0%
of users said the roll-on applicator made it easier to target their specific problem areas consistently.
0%
reported their scalp felt less oily and more balanced within the first two weeks of daily use.
0%
said they noticed their hair felt thicker and fuller after consistent nightly use.
* Based on internal studies and customer feedback surveys.
I've been dealing with thinning edges for two years and honestly felt like nothing was going to work at this point. A friend told me about this and I figured why not — worst case I'm out twenty bucks. About three weeks in I started noticing baby hairs I hadn't seen in a long time. I use it every night before bed and the fact that it doesn't leave my hair greasy is what keeps me consistent with it. Already on my second one.
What got me was the salicylic acid and niacinamide — I'd never thought about using actual skincare ingredients on my scalp before, but it makes complete sense. My scalp always felt a little itchy and congested and within a week of using this that basically went away. My hair feels fuller at the crown and I'm not losing nearly as much in the shower. Not a miracle, just something that's actually working.
I bought this mostly for the roll-on because I hate getting serum all over my hands. But it actually does what it says — I've been using it on my part line every night and my husband literally asked me if I'd gotten a haircut because my hair looked thicker. I'll take it. Clean formula, no gross residue, easy to use. Really happy with this one.
