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Lash Serum 101: Things No One Tells You

Growing Your Lashes Longer

So, you’ve finally decided to try a lash serum. Maybe you’ve always wanted super long lashes. Or you’re tired of using false lashes every time you go out with friends. Or maybe you’ve just seen way too many before and after shots of lashes from a certain skincare brand in your Facebook feed. But there are a few things you should know before you start using a lash serum. Or maybe a few things you should know about lash serum even if you’ve been using one for years.

Prostaglandins and analogues
Almost all lash serums work with a combination of vitamins, peptides and prostaglandin analogues. You can learn more about how prostaglandin analogues work in this post.

Lash serums aren’t pregnancy safe
So, because of various effects on both mom and baby, we don’t recommend prostaglandins during pregnancy. And while your lash serum has a very small amount and you use a very small amount, you likely won’t find a doctor who says it’s 100% safe. The study of lash serum safety would require a huge number of pregnant women, would be incredibly expensive, and likely would be unethical to perform. Personally, I stopped using my lash serum while pregnant and I recommend avoiding them when asked.

I have a list of pregnancy and nursing safe lash serums here.

Give it time
It will probably take a minimum of 6 weeks to really see results from your lash serum, maybe even 12. For real.

Expect some irritation
Every lash serum that I’ve tried has given me itchy, irritated lash lines. I’ve found that cleansing my lash line each night with baby shampoo and minimizing my eye liner helps quite a bit. It usually starts about 4-5 weeks after starting lash serum, lasts about 2 weeks, and then goes away.

Note that with each new tube of lash serum does this to me, even if I’ve been using that brand for years. The very first tube is the worst and subsequent tubes aren’t as irritating, but it still happens.

You can use more than one
Each brand of lash serum has different ingredients in the mix to support your lashes and improve their growth. The only harm in doubling up is that you’ll likely have more irritation. If this is tolerable, if it a try! I’ve done well with a combination of Revitalash Advanced and R+F Lash Blast.

Your lashes won’t be the same
After lash serum my lashes are definitely longer and thicker, but they’re also a bit harder to manage. They are straighter, less likely to curl, and those longer lashes are also harder to get mascara on to, they wiggle around a lot.

I’ve found that the stiffer rubber pad in the Surratt Beauty Relevee Lash Curler really does make a big difference over other lash curlers (yes, including the Shu and Shiseido). My lashes curl much more easily and hold that curl all day.

As for mascara, I’m now obsessed with the Bobbi Brown Smokey Lash Mascara. Something about the wand deposits mascara onto my wiggly lashes more easily, and it is stiff enough to not let my lashes straighten out throughout the day.

Use it on your brows
The ingredients in lash serums don’t only work on your lashes, they also work on your eyebrows. You can use the same lash serum on your brows to help fill in any bare spots.

Many lash serums also come in a brow version, typically this is is just a gel version of the liquid lash serum. I’ve found that the brow version stays put a bit better on the brows, rather than dripping down like the lash version.

Mascara Tip Guide
Read more about mascara, mascara primers and lashes in my Mascara and Lashes Guide

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About Me

I’m a doctor, a mommy and a bit of a beauty addict. If you let me, I can take 2 hours to get ready in the morning. Really. I'm on a quest for faster beauty that works!

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  1. 4.7.18
    Pam said:

    I loved reading this today as I just started with Latisse! I am only 2-weeks in. So, I am excited to start seeing results soon. I do have a bit of irriation and have been experimenting with ways to distribute the liquid better as the brushes that came with the Rx are terrible! I am now using an ultra thin eyeliner brush instead of the disposable ones that come with the Latisse and then I was it every night and let it air dry in-between uses. It distributes the product much better (concentrates it to the actual lash line) and avoids getting more liquid onto the skin on the lids.

  2. 4.7.18
    Debbie Mecher said:

    I loved using Revitalash which worked great on my lashes! Unfortunately, the product seemed to stopped working after I had been using it for a couple of years. Has anyone else had the same experience?

    • 4.7.18
      15mins said:

      I did! I swapped to R+F Lash Boost, and I can swap back and forth with Revitalash, but it really did just stop working for me after about 2.5 years. It’s like my lashes were just tired of it.

  3. 4.9.18
    Kirsten said:

    Is Latisse better than Revitalash and or Revitalash/R+F? I have short, fine, light brown lashes and there’s no way I could keep up with lash extension maintenance (I think). Even tho I have blue eyes, the rep at my derm was pretty clear on the iris color happening once during the trial and they implied it wasn’t actually Latisse. Eye definition makes such a huge difference for me, and I have to apply loads of mascara to have an impact (both Bobbi Brown and MUFE Smokey mascaras are great).

    • 4.9.18
      15mins said:

      So, I’ve heard from ophtho friends that they have seen iris darkening in some of their patients, though they watch closely for it and discontinue the Latisse if they see it.
      Latisse is the prescription version, so the prostaglandin analogue is stronger than the over the counter versions in Revitalash or R+F, but those versions also contain ingredients like peptides and antioxidants and I do think those help with lash growth as they help the skin in the area. Everyone’s lashes will respond differently to each product. If you’re worried at all about the iris thing happening, I would just pick one of the over the counter lash serums and go with it, if you aren’t getting the results you want after about 3 months I’d either add in or swap to a different one. 🙂

    • 10.24.19
      Kathryn Perks said:

      Hi! Would GrandeLASH-MD Ben pregnancy safe? Ingredients: Aqua, Glycerol, Glycosaminoglycans, Hyaluronic Acid, Butanamide, Leuconostoc/Radish Root Ferment Filtrate, Caprylyl Glycol, Sodium Benzoate, 2-Hydroxypropanoic Acid, Sodium PCA, Panax Ginseng Root Extract, L – Proline, Acathopanax Senticosus (Eleuthero) Root Extract, Hydrolyzed Yeast Extract, Chamomilla Recutita Flower Extract, Arctostaphylos Uva URSI Extract, Actiphyte Of Chamomile GL, Phenoxyethanol, Tocopheryl Acetate, Ethylhexylglycerin, Propylene Glycol, Hydroxyethylcellulose, Sorbitan, Gluconolactone, Triethanolamine, D-Glucitol, Leucidal Liquid, Geogard Ultra, Cloprostenol isopropyl ester GrandeBROW: Aqua, Glycerol, Glycosaminoglycans, Hyaluronic Acid, Hydrolyzed Yeast Extract, Panax Ginseng Root Extract, Acathopanax Senticosus (Eleuthero) Root Extract, Arctostaphylos Uva URSI Extract, Butanamide, Caprylyl Glycol, Chamomilla Recutita Flower Extract, Sodium Benzoate, Sodium PCA, Leuconostoc/Radish Root Ferment Filtrate, L-Proline, 2-Hydroxypropanoic Acid, Tocopheryl Acetate, Triethanolamine, Ethylhexylglycerin, Phenoxyethanol, Propylene Glycol, Hydroxyethylcellulose, Gluconolactone, D-Glucitol, Geogard Ultra, Sensiva SC 10, Leucidal Liquid, Cloprostenol isopropyl ester

      Thank you so much! I really appreciate all you do!

      • 10.26.19
        15mins said:

        It isn’t safe due to the gluconolactone in both the lash and brow, it’s ok for nursing

        • 3.31.20
          Amber M. said:

          Oh my gosh this is safe for breastfeeding!!! I used this for a few years and had to stop once I got pregnant and my eyelashes have literally fallen out. It’s embarrassing. I was hoping to not wait through a year of nursing while no eyelashes before restarting it!

          • 2.21.21
            Chelsea said:

            Your lashes “fell out” because the serum keeps them from shedding. That’s how they get so long. So when you stop use of the serum they go on to do what they are supposed to do.. which is shed.

        • 6.22.20
          Dee said:

          The ULTA and Sephora websites say to avoid GrandeLash while breastfeeding. Just wanted to see if you know why they put that on their website? I really want to use this lash serum but have hesitated because the website says to avoid it.

          • 6.22.20
            Christine said:

            Info here on why sometimes I disagree with brands: pregnancy beauty FAQ

          • 11.3.20
            Laura said:

            Box says not while pregnant or nursing. I’ve been nursing for 15 months lol on day I’ll be able to try it :/

  4. 4.10.18
    Kirsten said:

    Great to know about Latisse! I am more aware of how ingredients like peptides and antioxidants help the skin, and am fairly clueless on if/whether/how they help hair growth. I’ve often wondered if some companies even added them just because they sounded like or would be perceived as benefitial. Thanks!

    • 4.10.18
      15mins said:

      I asked a derm once if they actually do help hair growth and I guess the theory is that by supporting the skin and improving its overall health it is then able to support more hair growth 🙂

  5. 1.24.19
    Mimi said:

    I hope I found the right post! Is LashFood serum pregnancy safe?

    Water, Bergamot Peel Water, Lavender Flower Water, Citrus Orange Fruit Water, Butylene Gylcol , Paeonia Albiflora Root Extract, Panax Ginseng Root Extract, Trehalose, Aloe Barbadensis Leaf Juice, Hydrolyzed Rice Protein, Portulaca Oleracea Extract, Prunus Mume Fruit Extract, Xanthan Gum, Phenethyl Alcohol, Sorbic Acid, Hydrogenated Phosphatidylcholine, Potassium Sorbate, Arginine, Hydrolyzed Soy Protein, Adenosine, Lecithin, Coconut Fruit Juice.

    • 1.24.19
      15mins said:

      It’s ok!

      • 1.24.19
        Mimi said:

        Thank you so much!

      • 3.19.19
        Eli said:

        Is it also okay if you’re breastfeeding?

        • 3.22.19
          15mins said:

          should be

  6. 12.27.19
    DaleAnn said:

    Would the Milk eyelash serum be safe for nursing?

    Water (Aqua, Eau), Glycerin, Butylene Glycol, Polysorbate 20, Cannabis Sativa Seed Extract, Hydroxyethylcellulose, Phenoxyethanol, Caprylyl Glycol, Chlorphenesin, Papaver Somniferum Seed Extract, Aloe Barbadensis Leaf Juice, 1,2-Hexanediol, Hydrolyzed Quinoa, Sodium Hydroxide, Panthenol, Sodium Benzoate, Myristoyl Pentapeptide-17, Benzoic Acid, Potassium Sorbate, Biotinoyl Tripeptide-1, Oligopeptide-2, Nicotiana Benthamiana Hexapeptide-40 sh-Polypeptide-9, Nicotiana Benthamiana Hexapeptide-40 sh-Polypeptide-86, Citric Acid

    • 12.27.19
      15mins said:

      No, it has hemp in it which I recommend avoiding while pregnant. I need to finish my post on pregnancy safe lash serums!

    • 2.26.20
      Bernadette McNeil said:

      Is RFash boost okay while nursing? Thanks so much!

      • 2.26.20
        15mins said:

        It’s ok for nursing but not pregnancy

  7. 1.12.20
    Elise said:

    Is EssyNaturals pregnancy safe?
    Purified water, Alanine, isoleucine, Arginine, Glutamic acid, Serine, Valine, Lysine, Threonine, Aspartic acid, Histidine, Butanediol, Polygonum multiflorum extract, Nymphaea coerulea flower extract, Panax ginseng root extract, Hydrolyzed silk, Oligopeptide-1.

    • 1.12.20
      15mins said:

      This looks ok

      • 1.13.20
        Elise said:

        Thank you! It works so well for me and is a great price!

  8. 1.22.20
    MW said:

    Hi! Is Latisse safe while nursing?

    Active ingredient: bimatoprost

    Inactive ingredients: benzalkonium chloride; sodium chloride; sodium phosphate, dibasic; citric acid; and purified water. Sodium hydroxide and/or hydrochloric acid may be added to adjust pH.The pH during its shelf life ranges from 6.8 – 7.8.


    • 1.22.20
      15mins said:

      Probably fine while nursing, avoid while pregnant for sure.

  9. 3.13.20
    K said:

    I’m wondering if using a lash serum like Latisse would be okay during the first month of pregnancy i.e. before you know you are pregnant. Would this be considered safe if you stopped as soon as you had a confirmed pregnancy? Do you think it could do much harm in the first 3-4 weeks of pregnancy? Thank you so much. 🙂

    • 3.14.20
      15mins said:

      We recommend complete avoidance during pregnancy for one like Latisse.

      • 3.17.20
        K said:

        Okay, thanks for getting back to me… would you also avoid Revitalash in the first month of pregnancy, or do you think this one would be okay? I’m trying to find a lash serum that is safe but also effective! I really appreciate all of your info!

        • 3.17.20
          15mins said:

          Yes, definitely avoid revitalash.

  10. 3.31.20
    Amber M. said:

    I have read that StrongLash is considered pregnancy safe, but can’t find their ingredients list. Have you heard of this one?

    • 4.1.20
      15mins said:

      I haven’t.

  11. 4.19.20
    Jessica said:

    Would you know if NanoLash is safe? Also, their ingredient list seems oddly short, where is it best to find a comprehensive list of ingredients? Ingredients listed are:

    Aqua, Trifluoromethyl Dechloro Ethylprostenolamide, Euphrasia Officinalis Extract, Sodium Chloride, Alcohol Denat, Benzalkonium Chloride.

    • 4.20.20
      15mins said:

      Looks ok

  12. 5.26.20
    Dee said:

    Is the Neutrogena lash enhancer safe while breastfeeding?
    The ingredients are as follows:
    Water, Dipropylene Glycol, Pentylene Glycol, Glycerin, Carbomer, 1,2-Hexanediol, Panthenol, Ethylhexylglycerin, Aminomethyl Propanol, Glyceryl Polymethacrylate, Biotin, Propylene Glycol, Palmitoyl Tripeptide-1
    Thanks in advance!

    • 5.26.20
      15mins said:

      This is fine

  13. 5.28.20
    Liana said:

    I just want to say thank you for all the work you put into this! I used this while pregnant to look up all my skincare and everything was on here so easy to find, I love how you say why it’s not safe too. Now using this for breastfeeding products as well. I have recommended it to so many friends.
    Thank you xoxo

    • 6.5.20
      Fahida Hussain said:

      Is the UK lash serum safe to use during pregnancy?

      Purified Water (Aqua), Cucurbita Pepo (Pumpkin) Seed Extract, Vitis Vinifera (Grape) Seed Extract, Panax Ginseng Extract, Swertia Japonica Extract, Pentapeptide-17, Hyaluronic Acid (HA), Vitamin E (Tocopherol), Vitamin C (Ascorbic Acid), Vitamin B7 (Biotin), Vitamin B5 (Panthenol)

      • 6.5.20
        15mins said:

        This one looks fine to use during pregnancy and nursing

  14. 7.5.20
    Cheech said:

    Hi, this blog has been super helpful, was hoping that you’d be able to tell me if EyEnvy is safe to use while nursing. Ingredients are:
    Water (Aqua), Myristoyl Pentapeptide 17, Butylene Glycol, Dextran, Acetyl Tetrapeptide 3, Trifolium Pratense (Clover) Flower Extract, Glycerin, Panthenol, Sodium Citrate, Leuconostroc/Radish Root Ferment Filtrate, Polysorbate 20, Gluconolactone, Vitis Vinifera (Grape) Seed Extract, Caprylyl Glycol, Sodium Benzoate, Hydroxyethylcellulose, Propylene Glycol, Yeast Extract, Ethylhexylglycerin, Sodium PCA, Sodium Lactate, Chamomilla Recutita (Matricaria) Flower Extract, Panax Ginseng Root Extract, Arginine, Aspartic Acid, PCA, Hydrolyzed Glycosaminoglycans, Glycine, Alanine, Serine, Valine, Isoleucine, Proline, Threonine, Tocopheryl Acetate, Histidine, Phenylalanine, Sodium Hyaluronate, Arctostaphylosa Uva-Ursi Leaf Extract, Magnisium Ascorbyl Phosphate, Phenoxyethanol, Benzoic Acid, Sodium, Metabisulfite, Triethanolamine.

    Thank you in advance

    • 7.6.20
      Christine said:

      Looks ok for pregnancy and nursing

  15. 10.5.21
    Oly said:

    Hello! I just have a general question. There are claims out there that lash serums make your lids age/appear aged faster, because they dry your lids and also drain whatever liquid and fat there is, making lids even thinner than they are. Have you heard anything about this?
    Also, the only serum of the multiple ones I have tried that worked for me was LiLash, but it makes my already veiny lids even more burgundy because all the veins can be seen more. I assume that is because of all the blood flow to the lashes so they grow longer? Is there a way to avoid it and might it cause any issues in the future?

    • 10.5.21
      Christine said:

      Both of these things are known side effects of prostaglandins and their analogues. It is MUCH more likely to happen with latisse than an over the counter.

      It’s actually hyperpigmentation, not just changing the blood flow, and it’s somewhat thought to be reversible but isn’t always. The fat under the eyes actually can atrophy away (meaning, it basically dies), and that isn’t reversible though you can get tear trough filler that’s less visible. You can also get irritation/dryness/itchiness of the lids, that’s a temporary effect that goes away with continued use.

      Basically, all of these side effects are thought to be due to the prostaglandin analogues. To avoid you pretty much just need to use an over the counter version (I’ve only had irritation, never the other side effects personally, I only use over the counter), or if you’re still having issues then switch to a lash serum without a prostaglandin.

      • 10.5.21
        Oly said:

        Which one would be considered over the counter?
        And thank you very much for your responses and all the info on here!

        • 10.5.21
          Christine said:

          Anything you don’t need a prescription for is considered over the counter. So, everything except Latisse and other Bimatoprost products.

  16. 10.14.21
    Olivia said:

    Castor oil on lash line while pregnant is it safe?

    • 10.15.21
      Christine said: