Salicylic acid strengths and forms explained

Salicylic acid comes in many forms: face washes, pads, toners, serums, gels, creams, body washes, shampoos, wart plasters and office peels. The number on the label ranges from 0.5 to 40 percent between them, and so does how long the medicine stays on your skin. This guide sets out the strength the FDA allows for each use, what each form does, and how to pick one. For how the ingredient works, see the hub guide, what salicylic acid does for your skin.

The FDA ranges, by use

In the United States, the FDA sets a strength range for each type of over-the-counter product that contains salicylic acid. The ranges come from the federal rules for acne products, dandruff and psoriasis products, and wart removers.

Use	Strength allowed	Where it goes
Acne	0.5 to 2 percent	Face, chest, back
Dandruff, seborrheic dermatitis, psoriasis	1.8 to 3 percent	Scalp and skin
Common and plantar warts, liquid	5 to 17 percent	The wart only
Common and plantar warts, plaster	12 to 40 percent	The wart only

Two points follow from the table. First, the top of the acne range is 2 percent, so a face product that says 2 percent is at the upper limit and holds four times the salicylic acid of a 0.5 percent product. Second, anything above 3 percent sold without a prescription is a wart product. The wart rules require the warning "Do not use on moles, birthmarks, warts with hair growing from them, genital warts, or warts on the face or mucous membranes." MedlinePlus repeats that warts on the face should not be treated with topical salicylic acid.

A 2010 review whose first author is a retired FDA scientist adds that salicylic acid in cosmetics, the skincare that is not sold as a drug, is used at concentrations below 3 percent.

Rinse-off or leave-on

For acne, the most useful question about a product is whether it stays on your skin. The FDA's acne rules split products into two groups.

Leave-on products include gels, creams, lotions, serums, pads and toners that you do not rinse. The FDA requires these directions on the label: clean the skin first, "cover the entire affected area with a thin layer one to three times daily," start with one application a day because the skin can dry out, and "if bothersome dryness or peeling occurs, reduce application to once a day or every other day."

Rinse-off products include face washes, body washes and masks. The FDA says products like "soaps and masks, may be applied and removed and should include appropriate directions." So each wash writes its own directions, and you should read them.

A wash touches the skin for a short time before you rinse it away. A leave-on product sits on the skin until your next wash. Two products with the same 2 percent on the label can therefore act differently on the skin, and the leave-on one is more likely to dry it.

Face washes and cleansers

The American Academy of Dermatology (AAD) is positive about salicylic acid cleansers. Its page on large pores says: "Studies show salicylic acid can unclog pores. Some cleansers containing salicylic acid are gentle enough to use every day." If the cleanser dries or irritates your skin, the AAD suggests using a mild, non-comedogenic cleanser in the morning and the salicylic acid cleanser at night. Non-comedogenic means the product is made not to clog pores.

The same AAD page adds a limit: "Many people who have acne need more than salicylic acne to control their acne." A wash is a gentle way to start, and it may not be enough on its own for pimples that are red and swollen.

Wash with your fingertips and lukewarm water. The AAD says scrubbing irritates the skin, and advises limiting washing to twice a day and after sweating.

Pads, toners and wipes

MedlinePlus lists pads, wipes and cloths among the forms of topical salicylic acid. A pad or toner that you do not rinse off is a leave-on product, so the FDA's leave-on directions apply. MedlinePlus also warns against putting skincare products that contain alcohol on skin you are treating with salicylic acid, unless your doctor says to. Many toners contain alcohol, so check the inactive ingredients.

Serums, gels and creams

Serums, gels and creams stay on the skin the longest. The AAD's acne page says that salicylic acid is sold "in different strengths and in different forms, including cleansers and moisturizers." A moisturizer with salicylic acid is still an acne medicine, so count it as your one acne product.

This matters because the FDA requires every acne product to warn that "skin irritation and dryness is more likely to occur if you use another topical acne medication at the same time." A salicylic acid cleanser, a salicylic acid toner and a salicylic acid moisturizer used together are three acne medicines on the same skin.

Body washes

For acne on the chest, back and shoulders, a body wash is the easiest way to reach the skin. The AAD's page on acne caused by sports gear says "Using an acne medication with salicylic acid often works well to clear this type of acne," and adds that a dermatologist can help if the acne is still there after 6 to 8 weeks. That type of acne comes from gear and tight clothing trapping heat and sweat against the skin.

The AAD's back acne page names two other products it has studied for the back, a benzoyl peroxide foam wash and adapalene gel, and says anyone with deep, painful acne on the back needs a dermatologist. The same page warns that harsh soaps, scrubs, loofahs and back brushes can make acne worse. A salicylic acid body wash with scrubbing beads combines an acne medicine with a scrub, so a smooth wash is the gentler choice.

Spot treatments and patches

MedlinePlus lists patches among the forms of topical salicylic acid. A spot product puts the medicine on one pimple. The FDA's acne directions are written for the whole area where acne appears: "cover the entire affected area with a thin layer." A spot product reaches only the skin under it, so the rest of the area where you get acne stays untreated. Spot treatment in general is covered by another Skinli hub.

Shampoos

Salicylic acid shampoos treat the scalp. The FDA allows 1.8 to 3 percent for dandruff, seborrheic dermatitis and psoriasis. These are separate products with separate directions, and a shampoo that runs over the face and back does add salicylic acid to that skin.

Peels in a dermatology office

A salicylic acid peel is a treatment done by a dermatologist. A 2015 review in Clinical, Cosmetic and Investigational Dermatology describes the standard peel as a 20 or 30 percent solution, repeated every 2 to 4 weeks, with the best results after 3 to 6 peels. The review lists dryness, redness, peeling and crusting as possible side effects and names salicylate poisoning, where too much of the ingredient enters the body, as a rare but serious risk. The 2024 acne guideline from the AAD found too little evidence to make a recommendation on chemical peels. A peel at these strengths is a medical procedure, so do not try one at home.

How to choose

1. Pick the form you will use every day. A wash suits people who want the shortest contact with the skin. A leave-on product keeps the medicine on longer and is more likely to dry the skin.
2. Check the active ingredient line. For acne, look for salicylic acid between 0.5 and 2 percent.
3. Use one salicylic acid product at a time. A wash, a toner and a cream together are three acne medicines.
4. Start low and slow. The FDA directions say to start once a day. MedlinePlus says you may apply it less often at first and increase after your skin adjusts.
5. Give it time. The AAD says to use one product for 6 to 8 weeks before judging it, and complete clearing generally takes 3 to 4 months.

Before a leave-on product goes on your whole face, try the 3-day test from MedlinePlus: a small amount on one or two small areas for 3 days. The guide how to patch test a new skincare product covers the steps. For where a salicylic acid product fits in a full routine, see the complete acne skincare routine, and for daily use of the product you pick, see how to use salicylic acid on your face.