Drunk Elephant C - Firma Day Serum Review

For years, I’ve gotten my vitamin C fix from Paula's Choice C15 Booster. 

It’s a dupe for Skinceuticals CE Ferulic serum, the original CEF serum (CEF stands for vitamin C, vitamin E and Ferulic acid). Same benefits for way less than half the price.

Sure, I tried different vitamin C serums over the years (hey, I’m a skincare blogger – I can’t not cheat on my HGs!), but I always came back to Paula's Choice C15 Booster. I thought I always would.

Until Drunk Elephant C-Firma Day Serum finally hit the UK a few months. After testing it for a month, I’m not sure I want to go back to my first love this time. Here’s why:



Wondering what’s the best antioxidant out there?


None. When it comes to antioxidants, the more, the merrier. The more antioxidants you feed your skin, the more free radicals you destroy. It’s as easy as that.

One of the most powerful combinations of antioxidants is 15% vitamin C (ascorbic acid), 1% vitamin E (tocopherol) and 0.5% Ferulic acid. It’s the one you’ll find in Skinceuticals CE Feruice, Paula's C15 Booster and plenty of other vitamin C serums.

Ascorbic acid is an antiaging superstar. Studies show it can:

  • fight the free radicals that give you wrinkles
  • boost the production of collagen, the protein that keeps skin firm
  • reduces transepidermal water losshelping to keep skin hydrated
  • has skin-lightening properties that can fade away hyperpigmentation

Problem is, ascorbic acid is unstable AF. That means it loses its antiaging superpowers quickly. If it came in a see-through tube, you’ll see it turn brown (a sign it's going bad) within a few short days.

Drunk Elephant C-Firma Day Serum has the packaging nailed right to help vitamin C last as long as possible. Vitamin E and ferulic acid help with that too.

These two antioxidants don’t just fight their own free radicals too. They also help stablise vitamin C, making it last (and be effective) for longer. Plus, all 3 together help prevent sun damage.

P.S. Drunk Elephant gave ascorbic acid the best chance to last as long as possible. But this isn’t something you can buy now and use six months later or buy in bulk. It won’t go bad within a week but won’t last you for too many months either. Be quick!

P.P. S. This combination works best at a pH range between 2.5-3.5. Drunk Elephant C-Firma Day Serum has a ph of 3.5. The higher pH makes it less irritating than Skinceuticals CE Ferulic (pH 2.5-3) and Paula's Choice C15 Booster (pH 3).


CEF aren’t the only antioxidants in Drunk Elephant C-Firma Serum. It’d take too long to list them all (and this review is already long enough), so here are the highlights:

  • Green tea: it destroys free radicals, soothes inflammation and helps protects skin from sun damage
  • Licorice extract: it fights free radicals and fades away dark spots
  • Grape extract: another free-radical fighter with anti-inflammatory properties

See what I mean when I say that this vitamin C serum goes the extra mile? It’s half the price of Skinceuticals CE Ferulic yet it gives you way more antioxidants to prevent those pesky wrinkles.


Pumpkins ain’t just a Halloween treat. When fermented with lactobacillus lactic, they create an enzyme with exfoliating properties.

It works by breaking down keratin, the protein that keeps those dull and rough outer layers of your skin stuck on your face. Once those are off your skin, your face looks smoother and brighter.

I prefer glycolic acid (a member of the Alpga Hydroxy Acids family)  to do the job. But if you find AHAs too harsh for your skin – or simply don’t like the idea of using acids – this is a good alternative for you.

It goes without saying (but I’ll say it anyway) that if you want to use Drunk Elephant C-Firma Day Serum but aren’t ready to give up on exfoliating acids just yet, cut back on exfoliation.

Exfoliation ain’t like antioxidants. The more you exfoliate, the higher the chance of irritating your skin. Be careful!


I’m pairing them together because they both moisturize skin – just in different ways.

Marula oil is what gave Drunk Elephant its name. Legend has it, elephants get drunk when they eat too much marula fruit.

True or false, you can’t deny its benefits for your skin. Marula oil is loaded with moisturising fatty acids that create a barrier on the skin that slows down water loss. Plus, it has its fair share of antioxidants, too.

Hyaluronic acid, on the other hand, is a moisture magnet: it attracts moisture into the skin and binds it there. It’s so powerful, it can hold up to 1000 times its weight in water!


The only thing I DON’T like about Drunk Elephant C-Firma Day Serum? The texture’s a little sticky.

It still works well under sunscreen and makeup, but if you’ve got oily skin, this could be a dealbreaker for you. Try to get hold of a sample if you can.

Instead, don’t worry about the golden hue of the serum. Usually, that’s a sign vitamin C is already going bad, but that’s not what’s going on here. It’s the curcuminoids (a group of anti-irritants) that gives the serum its colour.

I use Drunk Elephant C-Firma Serum every morning to enhance the effectiveness of my sunscreen (CEF boosts photoprotection, remember?). But you can totally use it at night too if the stickiness bothers you that much.

After a few days, I’ve already noticed my skin getting brighter. It gives it a luminous, healthy glow I really like. If you’ve got any dark spots on your skin, it brightens those up and fades them away, too.

I’m also confident the serum is helping me keep premature wrinkles away. Antioxidants prevent wrinkles so you won’t see results anytime soon (in this area anyway).

But there’s plenty of research that shows the antioxidants Drunk Elephant picked work. That’s good enough for me.

I’m hooked. Don’t try it if you don’t want to get addicted too!

All comments (12)

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  • Jaqi Jones

    I think you can solve the problem of this vitamin C serum going bad by buying the smaller version of it which is available in the Littles or in some other gift packs I’ve never had a problem with us going bad or turning colors on me but perhaps since you live in the UK it’s sat around for a longer period of time then if you purchase it in the US that’s the only thing I can think of but I have heard a lot of people say that they’re drunk elephant vitamin C serum has gone bad so I don’t doubt what you’re saying is true but I’ve never had that experience myself

  • SweetPea V :)

    What a great review! I've been debating on getting Drunk Elephant C - Firma Day Serum ever since it popped up in my inbox from Sephora. I'm new to serums but i've been using Clarins Double Serum (Hydric+Lipidic System) with Curcuma Tumeric and i cant see going back to not including a serum in my routine! Unfortunately im nearing the end of my bottle and i was thinking about checking out what else is out there! You were extremely helpful! Thank you!

  • Micheala

    Thanks for the review

  • Christian Callaway

    Your review is amazing and so informative! I love how you described all the benefits to this product. A lot of ingredients in skincare I do not understand their benefits and love when ingredients are explained of how they help skin. Thank you so much for your helpful review, it looks like an awesome serum!

  • Misty

    Amazing review! I'm super sold!

  • Jennifer Henning

    This is a great review. I love the sounds of all the benefits of this serum. I've still never had or gotten to try a good serum like this. Wish I could maybe buy it someday.

  • Joyce McDaniel

    What a great review and I have been wanting to try Drunk Elephant for a while now. With this review I will try it. Thank you

  • Kelly K

    Thanks for the very through review. Lots of helpful information. I hadn't heard about this brand until recently and now I have to try!!!

  • Laury Dencklau

    Thanks for this review.

  • Quarterlife Balance

    Shout out for a fantastic, thorough review. I loved the Q+A built into your post. I have had my eye on Drunk Elephant and hope I can receive some of their products to try and review soon

  • Christy Sargent

    Serum is life! Thanks for the awesome review!

  • Melissa Griffith

    Great review!!! Ty 4 posting this was very informative. Now I understand why I like Drunk Elephants vitamin C serum so well, and why ever other C serum fails in comparison.

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