Crystal Retinal 24.

"Retinol is my personal favorite. This is 20% stronger than the next equivalent strength and it packs a punch. [...] I absolutely love it and it's just my personal favorite."

"It doesn't get stronger than this. I love the fact that it's encapsulated, which is going to reduce the risk of any side effects and irritation. And I like the fact that they've packed this full of antioxidants and hydrators to minimize the risk of any dryness or peeling, flaking that you might experience. [...] For the lovers of Medik8 out there that have tried the Medik8 Crystal Retinal line but want to go for the highest option, I would fully recommend this. It's roughly 20% stronger than their next one down, so that's a big jump. But as long as you've gradually gone up through the gradients, you should have no problem incorporating this."

"I've been using this product for the past month. [...] I'm an established retinoid user I've been using them for the past 6 years and so I didn't expect to see a whole lot of change with this product so I was pleasantly surprised when I genuinely did. I started to see the emergence of fine lines and wrinkles around the crow's feet, around the laughter lines and the 11s. I've also noticed a little bit of loss of firmness around the jawline. Whilst the results I saw from this weren't like transformative and game-changing, they were noticeable enough that I could see them with my own naked eye when I looked in the mirror. [...] One thing I did notice though is I did see an increase in dryness, sensitivity and irritation. That should be expected after all, I'm using a roughly 20% higher dose of retinoids in this versus what I was using before. [...] With a higher concentration you usually will see an increase in side effects and irritation. It wasn't particularly unpleasant or anything really to suggest that you shouldn't be using it but it's definitely something to be aware of. I think this is the sort of product that really should only be used by people that are established retinoid users, having incorporated them successfully probably for the past 12 months. [...] I wasn't wildly impressed with the price point."

"It's encapsulated and because it's a retinol you can use this with everything else. So I was definitely impressed by that. For me it really just comes down to the fact that if you want a little extra in terms of your anti-aging, reaching for a 20% stronger option definitely seemed to work for me. However, there are some cons. First and foremost, there was an increase in sensitivity. It was nothing unmanageable, my skin wasn't painful or super dry or anything like that, but I definitely noticed I got more sensitivity from this product than I did from other options. That's kind of to be expected, it's 20% stronger, but that sensitivity did last for about eight weeks. Something about two of three months I had that sensitivity and then my skin adjusted to it. This is something to definitely be aware of, and I think it means if you have any level of pre-existing sensitivity, this isn't probably going to be the product that you reach for. Also, the price point is quite prohibitive. I appreciate that they charge a lower cost for their lower strength and then the price builds as the strength builds. That makes sense because the key ingredient is driving a lot of that cost and you're using more of it in this product than you are in their lower strengths. So I don't mind the pricing structure, it just isn't going to be for everyone. I'm happy to spend on this because I really enjoyed it and I got those additional results, but I don't think everybody needs to."

"My personal favorite is the Medik8 Crystal Retinal 24. This is actually 20% stronger than the previous strongest retinal, so this really has stepped it up in terms of results, and you're going to get some next-level anti-aging, skin smoothing and pro-collagen benefits from this one. I absolutely love it. If you want the ease of over-the-counter, the Medik8 Crystal Retinal 24 is absolute perfection."

"I've been working through two of their retinol products. This is the Crystal Retinal 24 and their eye cream with retinaldehyde. One conversion away from the prescription formula tretinoin. Love both of these. They are a little bit on the colorful side. So you may want to consider letting this dry down for at least a half an hour before you jump into your white satin sheets."

"I've been able to tolerate the retin by Medik8. This is their 24 Crystal Retinal, their strongest that they make, but I've honestly been able to tolerate it even over the Tria laser treatments. I'm on level three and I've been doing it about five times a week."

"The Medik8 Crystal Retinal 24 is a powerful retinaldehyde. It's a nice hefty dose of retinol which is much gentler than tretinoin. It's the one that I use the nights that I'm not using my tretinoin. I always turn toward a retinol. But unfortunately, the pigment in this is so bright. It is bright orange and it doesn't dissipate throughout the evening. Retinol is on the yellow orange side, but this is really a powerful pigment and it's just hard to keep out of my hair and off my sheets. So I'm going to use this up, but slightly reluctantly."

"The Medik8 Crystal Retinal 24 has 0.24% retinaldehyde, so I believe it's probably the highest retinaldehyde concentration out there that I can think of nonprescription. It also contains cloudberry seed oil and vitamin E. It does contain vanilla and coumarin, which is [...] a fragrance ingredient that gives products a vanilla scent, [...] so it definitely has a vanilla scent in there, so keep that in mind if your skin is sensitive. [...] These are not cheap, they get to be pretty pricey."

"There's now two new versions from the last time I purchased it, they've got a 20 and a 24, and you guessed it, the 20 has 2% retinaldehyde and the 24 has 2.4% retinaldehyde. So these are not that strength. This one's the time I purchased it, the 10 was the highest you could get, but now I've got two higher strength. And if I'm correct, I believe the Medik8 24 is probably the highest retinaldehyde retinal out there that I can think of nonprescription. It also contains cloudberry seed oil and vitamin. They do contain vanilla, which is fine, but it also contains coumarin, which is technically a fragrance ingredient and it gives products a vanilla scent. So it's got vanilla and coumarin, so it definitely has a vanilla scent in there. So keep that in mind if your skin is sensitive. And you know, sometimes the prescription route can be kind of expensive for people, but if you start looking at some of these like the Medik8 ones, these are not cheap. They get to be pretty pricey. So in the long run, it might be better to maybe see a dermatologist or like an online consultation and maybe get something prescription if you're thinking about it. The Medik8 stuff is expensive."