How Long Does It *Actually* Take For Your New Skincare Product To Work?

“Expecting instant gratification from skincare is a recipe for disappointment,” Dr. Aanand Geria, M.D., F.A.A.D, tells me over email — which means that beauty enthusiasts living in the Instagram era (hi, hello) have probably experienced their fair share of disappointment. According to the dermatologist, it’s not realistic to expect visible results in a night, or even in a week. So how long does it take for skincare products to work? “The timeline to see results is entirely dependent on what kind of product you are using,” he says. “But I think 28 days is a good rule of thumb.” Yup, 28 whole days. Four whole weeks. One whole month. In other words: Patience might be the ingredient your skincare routine has been missing.

At first, the idea of a 28-day trial period might seem a bit random, but the number is significant in the skincare world: It’s the length of the typical skin cycle. One cycle accounts for the time it takes for a fresh skin cell to appear, mature, die, and shed — so theoretically, after 28 days, every single skin cell on the surface of your face will have had a chance to experience the efficacy (or lack thereof) of the product in question.

Of course, some ingredients work quicker than others. “Yes, there are some products out there, like physical exfoliants, that give instant results, but they are often temporary and superficial,” Tracy Julien, the Vice President of Marketing at beauty brand bioClarity, tells TZR. Dr. Geria says it can take as little as two weeks for cleansers, moisturizers, and spot treatments to earn a place in your permanent lineup. But deeper, long-term changes — like reducing acne or lifting hyperpigmentation — naturally take a little longer. Julien suggests thinking about it in terms of how the body heals from a cut or scrape. “The smaller the wound, the quicker it will heal and the larger or deeper the wound, the longer it takes to heal,” she says. “In the case of acne, the root cause of it is often subdermal, so it will take time for the active ingredients to penetrate into the dermis and reach the source of the inflammation and irritation.” BioClarity recommends customers give its proprietary Floralux complex, which features copper and chlorophyll to fight acne naturally, a full four to eight weeks to work.

That make seem like an interminable waiting period, but in the grand scheme of dermatology, it’s pretty reasonable, actually. “Products that contain retinoids, peptides, or growth factors can take up to three to four months to see the full effect, because they’re working on a genetic level,” Dr. Geria reveals. Glowing skin is a long game, and “allowing your skin adequate time to adjust to new products is essential,” he says.

However. When a product very clearly doesn’t work for your skin on the first try — if it stings or causes redness on application — there’s no need to give it 28 days to wreak more havoc. “The most immediate sign would be a burning or stinging sensation,” Dr. Geria says. “A little bit is ok, but if it persists for more than a minute or two, it is probably too irritating for the skin.”

Here’s where it gets complicated: A bad reaction to a certain product isn’t always about that certain product — it could be that its ingredients are interfering with another item in your routine, or you’ve over-exfoliated your skin and impaired its protective barrier. “For example, if a skin product is causing irritation, you may need to eliminate other sources of irritation in your regimen such as over-exfoliating or using harsh cleansers, which will then allow you to tolerate the new product better,” Dr. Geria says. “This ‘discovery’ phase can take several weeks to see how your products interact with each other.” For this reason, he recommends testing out no more than one new product every two weeks. (And even that’s pushing it.)

Even if you take all the right steps — you go slow, and keep new products to a minimum — you might notice an adverse reaction as you inch closer to the 28-day mark. “If it’s a new ingredient that the skin has never been exposed to, it can take several weeks to develop a reaction,” Dr. Geria says, as the skin approaches its tolerance threshold. “Allergic reactions usually manifest as scaly, red, itchy patches, but in severe cases, blistering rashes may develop as well swelling of the entire face.” If you notice any of that at any time, from Day 1 to Day 101 (and beyond), discontinue use of the new product immediately.

I’ll admit, this is possibly the most boring and anticlimactic skincare advice ever given. But if the end-goal is to find serums, moisturizers, masks, and more that actually work (and that is the end-goal, right?), slow and steady is the way to go. “If you are constantly changing and adding and subtracting new products into your routine, you just aren’t giving your skin a chance to adjust or make progress,” as Julien says. “With skincare, it is best to be consistent.” And patient, of course. It’s the secret ingredient.