Salicylic acid side effects: dryness to allergy

Most people who use salicylic acid notice some dryness or stinging, and most of it can be managed by using the product less often. A few side effects are rare and serious, and those need a doctor fast. This guide goes through each one, from the common to the rare, with what the sources say to do. For breakouts after starting salicylic acid, see can salicylic acid cause breakouts. For the ingredient in general, see the hub guide, what salicylic acid does for your skin.

Side effects at a glance

Side effect	How often the sources describe it	What to do
Dryness, peeling	Warned on every acne label	Use less often, add a moisturizer
Stinging, irritation	Listed by MedlinePlus as a side effect	Use less often. See a doctor if severe or it does not stop
Redness with burning	A sign of irritation	Cut back or stop. Stop other acne medicines on the same skin
Hives, throat tightness, swelling	Serious allergy, listed by MedlinePlus	Stop and get emergency help
Ringing in the ears, dizziness, fast breathing	Too much in the body, rare per a 2015 review	Call a doctor right away

Dryness and peeling

Salicylic acid loosens the dead skin cells on the surface of the skin. A 2015 review in Clinical, Cosmetic and Investigational Dermatology says it "decreases adhesion of corneocytes," the surface cells, and causes them to loosen. Some flaking follows from that.

The FDA's rules for acne products build dryness into the directions. They say to start with one application a day "because excessive drying of the skin may occur," and "if bothersome dryness or peeling occurs, reduce application to once a day or every other day." MedlinePlus says your skin "may become dry or irritated at the beginning of your treatment," and that you may apply the product less often at first and then more often once your skin has adjusted.

The American Academy of Dermatology (AAD) lists salicylic acid among acne treatments that "tend to dry and irritate the skin," and says: "Using a moisturizer every day can help your skin tolerate these medications." Pick a moisturizer labeled oil free or non-comedogenic, meaning made not to clog pores. The AAD adds a reason dryness matters for acne: "When your skin becomes dry, your body makes more oil. The extra oil can clog your pores."

Stinging, burning and redness

MedlinePlus lists two side effects of topical salicylic acid: "skin irritation" and "stinging in the area where you applied topical salicylic acid." It says to tell your doctor if either is severe or does not go away.

The FDA's page on BHA products is firmer: "If you use cosmetics with BHAs and experience skin irritation or prolonged stinging, stop using the product and consult your physician."

Irritation becomes more likely when you combine products. 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." MedlinePlus adds abrasive soaps, products that contain alcohol and medicated cosmetics to the list of things that can irritate skin treated with salicylic acid.

Steps if your skin stings or turns red:

1. Drop to once a day or every other day.
2. Stop any second acne medicine on the same skin.
3. Stop scrubs, rough cloths and alcohol toners.
4. Use a moisturizer twice a day.
5. Keep salicylic acid off broken or raw skin. MedlinePlus says not to apply it to skin that is "broken, red, swollen, irritated, or infected."

If the skin stays red and sore after these changes, stop the product and ask a doctor or pharmacist.

Sun sensitivity

Some acne and exfoliating products carry sun warnings, including benzoyl peroxide and the AHAs such as glycolic acid. Salicylic acid tested differently in one study. A 2009 study in the Journal of Dermatological Science treated test areas on the backs of 14 people with 10 percent glycolic acid, 2 percent salicylic acid or a plain base for 3.5 weeks. Glycolic acid increased redness, DNA damage and sunburn cells after light exposure. "Salicylic acid did not produce significant changes in any of these biomarkers."

The FDA still advises: "Use sun protection if you use a BHA product." Use a broad-spectrum sunscreen of SPF 30 or higher every morning, as the AAD advises for anyone treating acne.

Fabric and hair

Salicylic acid carries no bleaching warning. The FDA's acne rules require a warning to "avoid contact with hair and dyed fabrics, which may be bleached by this product" only on benzoyl peroxide products. The AAD says benzoyl peroxide "will bleach clothing, sheets, pillow cases, and towels." If your towels are losing color, look for benzoyl peroxide elsewhere in your routine. The guide salicylic acid vs benzoyl peroxide compares the two ingredients.

Allergic reactions

MedlinePlus lists the signs of a serious allergic reaction and says to "stop using salicylic acid and call your doctor immediately or get emergency medical help" for any of them:

• hives or itching
• throat tightness
• difficulty breathing
• feeling faint
• swelling of the eyes, face, lips or tongue

Before you start, MedlinePlus says to tell your doctor and pharmacist if you are allergic to salicylic acid or any ingredient in the product. The 3-day test on one or two small areas, which MedlinePlus recommends for first use, is the time to find a reaction before it covers your whole face. The guide how to patch test a new skincare product explains the test.

Too much salicylic acid in the body

Salicylic acid can pass through the skin into the body. MedlinePlus lists signs that call for a doctor right away: confusion, dizziness, extreme tiredness or weakness, headache, fast breathing, ringing or buzzing in the ears, hearing loss, nausea, vomiting and diarrhea. It gives the same list as the signs of an overdose, and says to call a poison control center if someone swallows salicylic acid or applies too much. In the United States the number is 1-800-222-1222.

How likely is this with an acne product? A 2003 review in the American Journal of Clinical Dermatology says salicylate poisoning "has occurred using methyl salicylate ointments and high concentrations of salicylic acid on widespread areas of hyperkeratotic skin," meaning thick, scaly skin, "but there are no known cases resulting from salicylic acid acne products." The 2015 review says absorption rises when salicylic acid is "kept under occlusion," meaning covered.

That is why MedlinePlus says not to apply salicylic acid to large areas of the body or cover it with a bandage unless a doctor tells you to. It also lists methyl salicylate muscle rubs and aspirin as products that may interact with topical salicylic acid, and says to tell your doctor if you have diabetes, or blood vessel, kidney or liver disease.

Higher strengths, higher risk

Over-the-counter acne products hold 0.5 to 2 percent salicylic acid. The FDA allows wart removers at 5 to 17 percent as a liquid and 12 to 40 percent as a plaster, and requires their labels to say not to use them on the face. The 2015 review lists redness, dryness, crusting and, rarely, salicylate poisoning among the side effects of 20 to 30 percent peels done in a clinic. Keep higher strengths off your face unless a dermatologist is doing the treatment.

Eyes, nose and mouth

MedlinePlus says to be careful not to get topical salicylic acid in your eyes, nose or mouth, and gives the fix if it happens: "If you accidentally get topical salicylic acid in your eyes, nose, or mouth, flush the area with water for 15 minutes." Keep a leave-on product clear of the eye area, and wash your hands after applying it.

Storage

MedlinePlus says to keep salicylic acid in its container, tightly closed and out of reach of children, and to store it "at room temperature and away from excess heat and moisture (not in the bathroom)." Check the expiry date printed on the package before you use an old bottle.

Children and teenagers

MedlinePlus says children and teenagers who have chickenpox or the flu "should not use topical salicylic acid unless they have been told to do so by a doctor," because of the risk of Reye's syndrome, a rare and serious illness that affects the brain and liver. The FDA advises avoiding BHA products on infants and children.

When to see a doctor

Get emergency help for signs of allergy. Call a doctor right away for signs of too much salicylic acid in the body. See a doctor or dermatologist for irritation that does not settle after cutting back, for deep, painful acne, or for skin that changes fast.