COSRX Pure Vitamin C 23% Serum with Vitamin E & Hyaluronic Acid, Brightening & Hydrating Facial Serum for Fine Lines, Uneven Skin Tone & Dull Skin, 0.7oz/20g, Korean Skin Care

I use this in the morning and I started noticing a difference after about a week. My eye bags were visibly brighter/glowy. Highly recommend for anyone with dark circles - it also feels very lightweight and absorbs into the skin quickly.

so it doesn't irritate sensitive skin (like mine). Unfortunately, unscented vitamin c smells like hotdog water 💔

I've been a huge fan of Cosrx products. I originally had used the lower strength of vitamin c and upgraded to this one a few months back. I feel that it does work in terms of discoloration, but for some reason this one makes me break out more than other vitamin c products I've used. I'm going to finish up what I have left of this bottle but I think I'll go back to the lower strength. My only complaint with the Cosrx vitamin c is how small the bottles are. It could be because vitamin c doesn't last long in terms of potency once opened, but it's a bit pricey for such a small bottle. You definitely have to keep it in the fridge and the smell is strange and not very pleasant but goes away shortly after application. I have not noticed any stinging or irritation from this higher strength vitamin c, but like I said, I have noticed acne break outs happening a bit more than before. My recommendation...give it a shot if you've already used the lower strength and feel you need more potency, but beware of potential break outs.

I’ve seen a lot of improvement in my skins texture and tone over the past 3 months. My skin Is much softer and my freckles and dark spots have become less noticeable. The serum is oily and spreads easily. It does have somewhat of an odor (like bread). I think for the price it’s great product.

After showering on a Friday evening, I applied the serum to my face. The smell was absolutely disgusting, but I was prepared for that having read the reviews. I had no negative skin reactions. A couple of hours later I started to get a headache. I took some ibuprofen, put the heating pad on my head, and went to sleep. I woke up at 3am with a terrible headache and I felt nauseous. I want to note that I get frequent migraines and that this was not a migraine headache. It was a painful tightness all around the top of my head. Also, I realized that the heat from the heating pad was reactivating the smell of the serum on my face, which was really gross. When I finally tried to get up and move around at 7am it was awful. I felt like I had the stomach flu. Sweating, shaking, nauseous. And then I threw up. I really did think I was sick and didn’t even consider the serum until a few hours later. I talked to my sister and mentioned my thoughts about the serum. She suggested that I take a long hot shower to try and get it all off of me and to change my bedding. So I did, and by the end of Saturday I was feeling not 100% but so much better. I haven’t seen any other reviews that mention this type of reaction. I tried googling it too and found nothing, so obviously this could be some kind of weird coincidence that I got sick for a short time while trying to use this product. Either way, I’m too scared to try it again. The smell alone might make me sick anyway. Good luck!

Can’t really rate how effective it is yet as I just got it. Did anyone else’s bottle fizz like opening a bottle of soda when you opened it? And everyone is right the smell is awful..

No

First time with this brand, but using Vit C serum for years.So far one of my favorites in the range of price. Smells uncomfortable fishy but that is the Vit C normal smell, after some seconds over the skin the smell is gone, and personally prefer this than any extra essence. The oil is pretty thin and absorbs immediately. Haven't had any reactions but I have quite of time with this VitC concentration. I like how my skin looks, give me a glossy renewed look every morning. Any result with dark spots or fine lines, but I realized that is normal aging and nothing to do with it lol, anyway my skin looks healthy and younger for my age. Totally happy with this brand in my second week of use.Update: one month of use and still love it!