Crystal Retinal 20.

"The Medik8 Crystal Retinal 20 is one of my absolute favorites. [...] Retinal, also known as retinaldehyde, which is what is in this, is just one step away from tretinoin or retinoic acid in your skin. Within your skin it goes retinol converted to retinaldehyde converted to retinoic acid which exerts the positive effect. Things like retinol and retinaldehyde can be a little bit unstable in skincare, and one reason why I am such a big fan of Medik8 is because they have a lot of technology surrounding how they are stabilizing their retinaldehyde within their formulation, and this is really important because you want to make sure that the concentration of retinaldehyde that it says you're getting on the package is actually reflected in what's going on your skin. Medik8 also does this really neat thing when it comes to formulating their retinoids which don't just formulate it at one potency. For example, this Crystal Retinal product exists at multiple strengths or concentrations of retinaldehyde. My holy grail is the retinaldehyde 20, which is the strongest form of retinaldehyde that I have ever seen available over the counter. For someone who maybe can't tolerate tretinoin or doesn't have access to tretinoin but is looking for something that is potent and is going to get the job done when it comes to helping with fine lines and wrinkles, textural problems, this is my go-to."

"I use this one by Medik8. This is their Crystal Retinal 20. So quite potent but just way less irritating. I love this formula. It's really nice and creamy. So you get kind of like a moisturization and anti-aging situation all in one. But I do a pump of this on my neck and a pump of this on my décolletté pretty much every single night. The other thing that I love about this is it comes in multiple strengths. So like I said, this is the 20, she's pretty strong. You could start at the level three or maybe even the level six and then as you go through a tube of that, you can graduate to the next strength and the next strength and maybe one day you work all the way up to prescription tretinoin. And if you can't quite get there, it helps you find the most effective and the most potent retinoid that you can handle."

"My retinoid of the year is by Medik8, it's their Crystal Retinal 20. [...] I feel like they do a really good job with their formulations and they're pretty famous in the retinoid space for formulating really stable retinoids and that's really important because these are vitamin A derived molecules that help stimulate collagen and prevent collagen breakdown, but if not formulated well that retinoid can break down in the formula and not exert any positive effects. This Crystal Retinal 20 is the strongest retinoid topical that Medik8 makes currently, I'm pretty sure it's 0.2% retinal, and [...] retinal is a step up in terms of efficacy and strength from retinol. [...] Retinol [...] gets converted into retinaldehyde in the skin and then retinaldehyde gets converted into the active retinoid which is retinoic acid, and so because retinal is closer to that active form it can be more effective and actually can cause less irritation for people too. It really plays nice with others, it never peels up or balls up on the skin when I apply my sunscreen. The one thing I'll say about this, and this is really only if you're like a real stickler for texture, is occasionally it feels a bit tacky or sticky on the skin and some days I don't really love that and other days it really doesn't bother me. I use it when my skin is feeling more sensitive and I want to take it back a notch from my prescription retinoid."