How to use salicylic acid on your face

Salicylic acid works best when you use it the way the label says, and the label is short. This guide turns the FDA's required directions and the advice from MedlinePlus and the American Academy of Dermatology (AAD) into plain steps: how to test it, how much to use, where it goes in your routine, what to keep off the same skin, and how to adjust if it stings. For what the ingredient does, see the hub guide, what salicylic acid does for your skin. For morning or night and how many times a week, see when to use salicylic acid.

Before the first use: the 3-day test

MedlinePlus says: "Apply a small amount of the salicylic acid product to one or two small areas you want to treat for 3 days when you begin to use this medication for the first time. If no reaction or discomfort occurs, use the product as directed." The FDA allows acne labels to print the same test as a "Sensitivity Test for a New User," and the FDA's page on BHAs, the group salicylic acid is sold under, also says to test on a small area before a large one.

Stinging can happen, and MedlinePlus lists it as a side effect. Stop and wait if you see redness that spreads, swelling, itching or hives. MedlinePlus says hives, throat tightness, trouble breathing, feeling faint or swelling of the eyes, face, lips or tongue need emergency help. The guide how to patch test a new skincare product goes through the test in more detail.

The label directions

Every leave-on salicylic acid acne product in the United States follows the FDA's rules for acne products. The required directions are:

• "clean the skin thoroughly before applying this product"
• "cover the entire affected area with a thin layer one to three times daily"
• "because excessive drying of the skin may occur, start with one application daily, then gradually increase to two or three times daily if needed or as directed by a doctor"
• "if bothersome dryness or peeling occurs, reduce application to once a day or every other day"

Face washes, body washes and masks are rinsed off, and the FDA lets those write "appropriate directions" of their own. So read the label of the exact product you bought. MedlinePlus says to read the package label with care, because "The label will tell you how to prepare your skin before you apply the medication, and exactly how you should apply the medication."

Step by step, leave-on product

Use this order for a gel, serum, pad, toner or cream that stays on the skin.

1. Wash. Wet your face with lukewarm water and apply a gentle cleanser with your fingertips, as the AAD describes on its face washing page. Do not scrub. Rinse with lukewarm water and pat dry with a soft towel.
2. Apply a thin layer. Cover the whole area where you get acne, for example the forehead, nose and chin, and the cheeks if you break out there. A thin layer is enough. MedlinePlus says to use the amount the label directs and not to use it more often than directed.
3. Keep clear of the eyes, nose and mouth. MedlinePlus says to flush with water for 15 minutes if salicylic acid gets into them.
4. Moisturize. The AAD lists salicylic acid among acne treatments that "tend to dry and irritate the skin," and says a daily moisturizer helps skin tolerate them. Choose one labeled oil free or non-comedogenic, meaning made not to clog pores.
5. Sunscreen in the morning. The FDA advises: "Use sun protection if you use a BHA product."
6. Wash your hands.

Step by step, salicylic acid cleanser

1. Wet your face with lukewarm water.
2. Apply the cleanser with your fingertips. The AAD says using a washcloth, mesh sponge or anything other than your fingertips can irritate your skin.
3. Follow the label for how long to leave it on before rinsing.
4. Rinse with lukewarm water and pat dry.
5. Moisturize.

The AAD's page on pores says some salicylic acid cleansers "are gentle enough to use every day." If the cleanser dries or irritates your skin, it suggests a mild cleanser in the morning and the salicylic acid cleanser before bed. The AAD also says to limit washing to twice a day and after sweating.

Where it fits in your routine

Step	Morning	Night
1	Gentle cleanser, or salicylic acid cleanser	Gentle cleanser, or salicylic acid cleanser
2	Leave-on salicylic acid product, if you use one in the morning	Leave-on salicylic acid product
3	Moisturizer	Moisturizer
4	Sunscreen, SPF 30 or higher	None

Use one salicylic acid product at a time. A salicylic acid wash, toner and serum used together add up to three acne medicines on the same skin. The guide what order to apply your acne products explains the reasoning behind this order.

What to keep off the same skin

MedlinePlus lists what not to apply to skin you treat with salicylic acid, unless a doctor tells you to:

• abrasive soaps or cleansers, such as scrubs with beads
• skin care products that contain alcohol
• other medicines for the skin, such as benzoyl peroxide and tretinoin
• medicated cosmetics

MedlinePlus warns that your skin may become irritated if you apply any of these to skin you treat with salicylic acid. The FDA requires every acne product to carry a similar warning: "skin irritation and dryness is more likely to occur if you use another topical acne medication at the same time. If irritation occurs, only use one topical acne medication at a time."

Skinli's photo plan uses adapalene 0.1 percent and benzoyl peroxide 2.5 percent, and it asks people to stop salicylic acid while they use those two gels for that reason. Skinli has separate guides on using salicylic acid with retinol and salicylic acid with niacinamide.

Where not to put it

MedlinePlus gives four limits:

• "Do not apply topical salicylic acid to skin that is broken, red, swollen, irritated, or infected." That includes pimples you have picked.
• "Do not apply topical salicylic acid to large areas of your body unless your doctor tells you that you should."
• "Do not cover the skin where you applied topical salicylic acid with a bandage or dressing unless your doctor tells you that you should."
• Do not swallow it.

A 2015 review in Clinical, Cosmetic and Investigational Dermatology says skin absorbs more salicylic acid when it is kept under a covering, and that poisoning from salicylic acid absorbed through the skin is rare but serious. MedlinePlus lists signs of too much salicylic acid: confusion, dizziness, extreme tiredness, headache, fast breathing, ringing in the ears, hearing loss, nausea, vomiting and diarrhea. Call a doctor right away if any appear.

Keep a simple record

Write down the date you started, the product, and how often you use it. Take a photo in the same light on day one and every two weeks after. The AAD says to use one product for 6 to 8 weeks without adding another, and a record shows whether a change in your skin came after a change in your routine. The guide how to take acne progress photos explains how to take photos you can compare.

If it stings or dries your skin

MedlinePlus says your skin "may become dry or irritated at the beginning of your treatment." It suggests two fixes: apply the product less often at first and build up once your skin has adjusted, and apply it less often again if dryness comes back later. The FDA directions say the same in numbers: once a day, or every other day.

MedlinePlus lists stinging where you applied the product as a side effect, and says to tell your doctor if skin irritation or stinging is severe or does not go away. The guide salicylic acid side effects covers what each reaction means.

How long before you judge it

MedlinePlus says it may take "several weeks or longer" to feel the full benefit, and that your skin may look worse in the first few days. The AAD says to use a product for 6 to 8 weeks, since "It takes that long to see some improvement," and complete clearing generally takes 3 to 4 months. Keep the same product and the same schedule for that time. See a doctor sooner for deep, painful lumps, acne that leaves scars, or skin that gets worse after the first weeks.