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Living with psoriasis doesn’t necessarily mean you have to overhaul your skin- or scalp-care routine. Psoriasis is caused by immune system dysfunction, not external irritants, so you can use many topical products safely as long as they don’t cause skin damage. However, anything with the potential to cause trauma to the skin—like a potent acid or strong surfactant—could spell trouble.
One reason topicals can lead to flare-ups is the Koebner phenomenon, which is when “local trauma stimulates the immune system to develop psoriasis in the traumatized skin,” says Shira Y. Wieder, MD, a board-certified dermatologist at Montefiore Einstein Advanced Care in New York City. When this happens new plaques appear in “healthy” areas of skin where there was previously no visible psoriasis.
The Koebner phenomenon does not affect everyone with psoriasis; frequently cited research estimates it occurs in about 25% to 30% of patients. “Not everyone with psoriasis has this response, but if you’ve ever watched a plaque appear at a cut, a scratch, or a sunburn, assume you’re someone who does,” says Omar Noor, MD, a New York City-based board-certified dermatologist.
Even if you don’t experience Koebnerization, applying a potentially irritating product to an area with visible psoriasis could worsen an existing flare-up. “If you have sensitivity [to an ingredient], then, yes, that’s going to trigger irritation to your skin, which will result in a flare in your psoriasis,” says Divya Shokeen, MD, a board-certified dermatologist and the founder of OSVI Dermatology and Surgical Institute in California. That’s why it’s important to do a small patch test anytime you try a new product to see if it triggers a reaction.
Overall, there’s a pretty big risk difference for patients whose psoriasis is controlled with medication or other treatments and those whose psoriasis isn’t. “If you haven’t found a treatment that controls your psoriasis yet, your skin is already primed to react, and a product that causes even mild trauma can seed a new plaque at that spot,” Dr. Noor says. “If your psoriasis is controlled, especially on a systemic treatment like a biologic, that risk drops substantially, but not to zero.” The key is knowing what’s likely to irritate your skin during a flare and what may spark an issue day-to-day even when your skin is clear.
Dr. Noor says patients with psoriasis in general should prioritize hydration in their skin-care routine. This can help soften plaques, improving both their appearance and any discomfort they cause. If you want to experiment with other types of ingredients—or are eager for a new tattoo or hair color—here are some guidelines on what you should approach with caution.
Meet the experts:
- Tracy Evans, MD, is a board-certified dermatologist and the medical director of Pacific Skin and Cosmetic Dermatology in California.
- Omar Noor, MD, is a New York City–based board-certified dermatologist.
- Divya Shokeen, MD, is a board-certified dermatologist and the founder of OSVI Dermatology and Surgical Institute in California.
- Shira Y. Wieder, MD, is a board-certified dermatologist at Montefiore Einstein Advanced Care in New York City.
1. High Concentration Skin Care Acids
Every dermatologist we spoke to brought up alpha-hydroxy acids (AHAs) and beta-hydroxy acids (BHAs). This includes glycolic, lactic, mandelic, and L-ascorbic acids.
“Psoriasis typically [causes] thick, scaly plaques,” Dr. Noor says. “There’s this misconception that the skin is thicker, so therefore you need to use stronger products in order to improve your skin.” While some skin-care acids can help manage psoriasis (more on that in a moment), the doctors caution against any product with a formula that contains a high percentage of these ingredients.
“AHAs and BHAs work by breaking down the bonds that hold dead surface cells together,” Dr. Noor says. “At higher strengths, or on skin that’s already inflamed, they [can] reach deeper than intended and can cause genuine injury.” This can lead to Koebnerization or worsen an existing flare-up.
Although everyone’s tolerance is different, Dr. Noor says that for leave-on products, he generally recommends patients with psoriasis stick to formulas with 5% or less glycolic acid, about 8% or less lactic acid, or up to 10% mandelic acid. Dr. Shokeen also advises against using L-ascorbic acid (the purest and most potent form of vitamin C) at concentrations of 15% or higher, which she says can be very irritating.
One skin care acid of note that’s an exception to this rule is salicylic acid. The dermatologists Allure spoke to agree that it could actually help treat psoriasis symptoms—as long as it’s paired with moisturizing ingredients. “Salicylic acid can be very drying for some people, [but] it can also be great for psoriasis because it’ll get rid of all the scale,” Dr. Wieder says. “We use lots of moisturizers imbued with salicylic acid” for psoriasis patients, she adds.
Dr. Shokeen says careful use of salicylic acid can even improve the effectiveness of topical psoriasis treatments. “Our skin is very good at keeping things out,” she says. “Salicylic acid will allow for a gentle exfoliation of that top layer to allow better penetration of ingredients [found in commonly prescribed psoriasis treatments] like steroids, vitamin D, and analogues [such as] calcipotriene … that can help decrease that inflammatory response.” Like with other skin-care acids, stick to formulas with a low concentration of salicylic acid—Dr. Shokeen says 2% in over-the-counter products is generally safe for most patients.
2. Chemical peels
This caution about many skin-care acids extends to chemical peels, which are usually made from a combination of acids in high concentrations. “Anything that’s going to break the barrier of the skin could result in psoriasis flaring more,” says Tracy Evans, MD, a board-certified dermatologist and the medical director of Pacific Skin and Cosmetic Dermatology in California. And that’s exactly what a peel does. “By definition a chemical peel [impairs the skin barrier],” Dr. Wieder says. “That’s the whole point of it. It’s a limited damage to the upper layers of the epidermis so that they exfoliate off.” Dr. Wieder says medium-depth and deep peels should raise red flags for psoriasis patients, although she notes she’d be less concerned about someone whose psoriasis is well-controlled with biologic medication opting for these treatments.
3. Physical exfoliants
Much like their chemical cousins, physical exfoliants are something you might assume would be helpful but can actually make things worse. “Psoriasis patients come in every day thinking they have to scrub off the scales,” Dr. Noor says. “They use walnut shells, apricot scrubs, and they’re just going to town with a loofah.”
While this approach could temporarily exfoliate away some scales, it might ultimately exacerbate your psoriasis or trigger new patches, as the scrubby bits can cause tiny cuts and scratches on the skin.
4. Abrasive in-office treatments
If exfoliating scrubs—which only remove the surface layer of skin—are risky for psoriasis, it makes sense that stronger in-office treatments like microneedling and certain lasers could also cause problems. “You can’t treat your skin with sandpaper,” Dr. Noor says. “You don’t want to sandblast your skin with all these exfoliants or some of these devices.”
Again, if your psoriasis is well-controlled, there’s less of a risk of a flare-up, but “if you feel like you are flaring, I would avoid the treatment altogether,” Dr. Evans says.
It’s worth noting that some laser treatments have been shown to successfully treat psoriasis when used with caution. “We have seen specifically that excimer treatments for redness can be very effective in psoriasis patients,” Dr. Noor says.
5. Strong surfactants
Since hydration should be one of the number one skin-care goal for psoriasis patients, using intense cleansers could lead to trouble. “You may want to be a little more cautious around harsh chemicals like surfactants that really strip the skin of oils,” Dr. Wieder says, noting that this impairs the skin barrier.
Dr. Noor specifically cautions against cleansers that “lather like dish soap,” which can signal that the product is heavy on surfactants like sodium lauryl sulfate (SLS). Surfactants strip away the good lipids, ceramides, and moisturizing factors in our skin, he explains. “If your soap lathers like dish soap, it’s no good because you’re treating your skin like a dirty pan, which we don’t want,” Dr. Noor says. He recommends gentle cleansers with hydrating ingredients, such as Cetaphil Gentle Skin Cleanser, which provides hydration without stripping the skin’s natural moisture barrier.
6. Fragrance and unscented products
Fragrance can be a bit tricky for people with psoriasis. Some patients might be totally fine with scented products, while others may be sensitive to them. If you fall into the latter camp, a fragrance could trigger a flare-up, just like any other ingredient that sparks sensitivity, Dr. Shokeen says.
Perhaps a bit counterintuitively unscented products can also be a cause for concern. “Unscented usually means that the companies are using chemicals to hide the scents,” Dr. Noor says. “Those chemicals can make the products worse for you if you have psoriasis. What you want to look for is ‘fragrance-free.’”
7. Pure essential oils
While products with all-natural ingredients might seem better for sensitive skin, dermatologists typically warn against them for patients with psoriasis. “Botanical doesn’t always mean benign,” Dr. Noor says. “Poison ivy is 100% natural.”
Tea tree oil, peppermint oil, menthol, and witch hazel are four natural ingredients to watch out for. “These can be really inflammatory,” Dr. Shokeen says. “They can trigger an immune response on your skin, which can then flare your psoriasis.” She says patients sometimes apply cooling menthol creams to plaque flare-ups in an attempt to calm the area—but it might actually make things worse.
“People love the concept of the tingling sensation,” like the feeling you get when you apply a product that contains peppermint oil, Dr. Noor says. “Tingling is not good with psoriasis.”
8. Lightweight moisturizers
Any moisturizer is better than no moisturizer for someone with psoriasis, but some will be more effective than others. One way companies make creams thinner is by adding alcohol, Dr. Noor says. This might make for a nice, lightweight lotion, but it can also further dry out psoriatic skin.
Dr. Noor recommends looking for richer creams with multiple lipids. “Nothing that comes out of a pump,” he says. “You have to thin the lotions out to get it out of a pump.”
9. Hair dyes
Some patients can be allergic to certain hair-dye ingredients. Dr. Noor says para-phenylenediamine (PPD) is a common one that causes issues. For someone without psoriasis having a reaction to PPD could just mean a few days or weeks of irritation. “The problem is the allergic reaction in a psoriasis patient creates an inflammatory mess,” Dr. Noor says. “The immune system is already edgy when you have psoriasis.” Introducing an ingredient you’re allergic to can “cause more psoriasis, more misery, and really make things more difficult to keep under control,” he says.
10. Tattoos
While tattoo ink can also cause allergic reactions, it’s the physical act of tattooing—a needle poking into your skin over and over and over—that’s more likely to be an issue for a psoriasis patient who experiences Koebnerization, Dr. Noor says. “[That] environment creates microtrauma that can trigger more psoriasis,” he explains. “It’s a bummer.”
Dr. Wieder also advises patients with psoriasis to approach tattoos with caution. “I’ve seen people develop psoriasis in the shape of their tattoo,” she says.
However, that doesn’t mean everyone with psoriasis should steer clear of building a body-art collection. Dr. Noor says that there are many great injectable and oral medications that can significantly subdue psoriasis patients’ dysregulated immune system, therefore reducing the chance of an inflammatory response. These treatments “allow you to get tattoos … and not have to worry about developing psoriasis in the tattooed areas,” he says.
And that brings us back to the top skin-care takeaway for anyone with psoriasis: The first step in your routine is to get the condition under control. “When you have psoriasis you should see a dermatologist,” Dr. Evans says. The doctor will help you settle on a treatment plan that works and identify any ingredients you’re still sensitive to, regardless of how well-controlled your psoriasis is. Those trigger ingredients aside, Dr. Evans says, “once your disease is under control, you pretty much can use what you want.” Just make sure to do a patch test before you go all in.
