Truly Works!
"I buy this on repeat. When I use it regularly, there is a noticeable difference in my eyebrow growth. They had become sparse over the last few years but this does the trick. They are thicker and darker. Love it!"
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A brow-and-lash-boosting serum powered by peptides and vegan keratin to accelerate the appearance of fuller, feathery brows and longer, thicker lashes.
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Suitable for
Lashes and brows.
Why we stand behind it
Featuring a unique two-in-one applicator to maximize both your brows and lashes, this serum creates the perfect environment for hair to thrive with a clean, 97 percent naturally derived, hyaluronic acid-powered formula with vegan keratin and a trio of peptides. It is also ophthalmologist tested, safe for sensitive eyes, and prostaglandin-free. Use it consistently on a daily basis for 12 weeks to see best results.
Key ingredients
Peptide trio: Promotes the look of length and thickness.
Vegan keratin: Provides essential building blocks of healthy-looking, fortified hair.
Provitamin B5: Promotes smooth, shiny hair.
this product meets
The Credo Clean Standard™
Every product we offer meets our industry leading standards for safety and sustainability.
learn moreThis product is
Cruelty Free
Vegan
Fragrance Free
Paraben Free
An undertone is the color beneath the surface of your skin, which never changes (even with a tan). There are three types of undertones:
Pink/Cool
I see red or pink undertones around the perimeter of my face and neck.
My skin burns easily, but barely tans.
My skin looks better in silver jewelry than gold.
Neutral
I see both pink and yellow undertones around the perimeter of my face and neck.
My skin sometimes burns and sometimes tans.
My skin looks good in both gold and silver jewelry.
Yellow/Warm
I see yellow or golden undertones around the perimeter of my face and neck.
My skin rarely burns, but tans easily.
My skin looks better in gold jewelry than silver.
Find your shade match
Take our 1 minute quiz and get matched to real people with your skin tone and type.
Apply nightly.
Use flatter side of applicator to coat entire brow area.
Angle the pointed tip to apply along top lash line.
Avoid applying near inner-eye corner or inside waterline.
Start with clean, dry face and wait one to two minutes for serum to dry.
Apply a thin layer to the roots of upper lash line.
Only use one dip of serum for each brow and lash (a little goes a long way).
Don’t apply makeup immediately after.
Don’t apply to bottom lashes (upper application takes care of your lower lashes).
Don’t skip days-that’ll just delay your visibly full, fluffy results.
We co-founded the nonprofit Pact to demystify how to recycle your beauty packaging empties and divert waste from landfills.
How to recycle your empties
1. Disassemble and clean all components
2. Pick the right disposal bin
3. Drop off your empties at your nearest Pact bin
1 Product Recycled = 10 Credo Rewards Points
create accountClean Makeup for Skincare Freaks. Welcome to next-level clean beauty that’s about revealing, expressing, and feeling comfy in your skin. It’s good makeup (not no makeup) that’s quick, easy, can’t mess it up. And it’s clinically proven to actually make your skin better, even when it’s bare. So you can look like your favorite self every single day.
SHOP ALL KosasOverall rating: 4.225806 / 5 from 31 reviews.
GrowPotion Fluffy Lash + Brow Boosting Serum is a dual-purpose serum designed to enhance the appearance of both brows and lashes. It features a unique applicator and a formula rich in peptides, vegan keratin, and hyaluronic acid, which is 97% naturally derived. Users have reported mixed results, with some experiencing fuller brows and others noticing thin hairs, but many appreciate the noticeable difference after consistent use.
Review topics: ["results","hair","difference","works","serum","brows","growth","application","lashes","eyebrows"].
"I buy this on repeat. When I use it regularly, there is a noticeable difference in my eyebrow growth. They had become sparse over the last few years but this does the trick. They are thicker and darker. Love it!"
— Tari J. (5/5)
"sad that the applicator broke the first week I used this and it was a gift. can’t speak on the product except that it seems to work for other people and I liked that it dried nicely without any stickiness"
— N (3/5)
"great brow serum!"
— Alena (5/5)
"I LOVE Kosas but this serum is a dud. I used it daily and never noticed any new growth."
— Leslie (2/5)
"I’ve been using this product for about two weeks and already I notice a slight difference in the fullness of my brows and the length of my lashes. It does leave a residue on my face that I have to wash off in the morning, which adds an extra step to my routine because previously I wasn’t using a facial cleanser in the morning. It’s not bad though."
— Maria S. (4/5)
"Only used on eyebrows, saw some new hair growth in areas that are normally barren but also got more pimples on my forehead directly above eyebrows when I use this serum. Be sure to wash it off thoroughly in the morning and be diligent about salicylic or oil/acne inhibiting products to combat. When the serum dries in my brows they feel stiff so I’m hesitant to use it on my lashes because I wouldn’t want them to be bent or break off."
— Karalyn (3/5)
"I didn't personally notice a difference with this product"
— Jen (2/5)
"Not actually sure it does anything, but I like it in theory."
— Shelly (3/5)
"This actually works!"
— CASEY R. (5/5)
"I've only used this on my eyebrows and saw some new hair growth in areas that are normally barren however I also get more pimples on my forehead directly above my eyebrows when I use this serum. I have an oily T-zone. Be sure to wash the serum off thoroughly in the morning and be diligent about salicylic or oil/acne inhibiting products to combat this. When the serum dries in my brows they feel stiff so I’m hesitant to use it on my lashes because I wouldn’t want them to be bent or break off. I don't plan to repurchase this product."
— Karalyn (5/5)
We offer clean beauty vetted to the highest standard.
We want to know where ingredients come from and how they were made.
Clean beauty should include the just treatment of humans and animals.
We co-founded Pact to tackle beauty’s packaging waste problem.
This product is: A brow-and-lash-boosting serum powered by peptides and vegan keratin to accelerate the appearance of fuller, feathery brows and longer, thicker lashes
Good for: Lashes & Brows
Why We Love It: Kosas GrowPotion Fluffy Lash + Boosting Serum features a unique two-in-one applicator to maximize both your brows and lashes. This serum creates the perfect environment for hair to thrive with a clean, 97 percent naturally derived, hyaluronic acid-powered formula with vegan keratin and a trio of peptides. It is also ophthalmologist tested, safe for sensitive eyes, and prostaglandin-free. Use it consistently on a daily basis for 12 weeks to see best results.