women's assorted cosmetics

The caustic nature of sodium hydroxide, a common ingredient in many skin care products, can make it seem scary. Although there is some risk, sodium hydroxide is generally safe.

Here are the facts about sodium hydroxide and skin care products.

Skin care 101: Sodium hydroxide

What is it used for? It helps oils and fats to form soap through saponification.

Which skin care products contain it? It can be found in makeup cleansers, and soaps.

What side effects can sodium hydroxide cause? It can cause chemical burns, rash, and even holes in the skin when used in high amounts.To avoid this, it is used in very small quantities in skin care products.

It is safe for skin care? Because of its small amount, sodium hydroxide can be considered safe for skin care. A patch test is a good way to check for adverse reactions.

What is sodium hydroxide?

Sodium hydroxide, also known as lye, caustic soda, is a white solid compound that absorbs water. It has a pH 14 and is alkaline. This helps to balance the pH of skin products when it’s used in very small amounts. (Psst: Think of alkaline, also known as basic, as the antithesis of acidic.)

It is also the main ingredient that helps oils and fats become one in cleansers and soaps. It is also used in body and facial care products.

Because of its basic properties, sodium hydroxide is a great addition to cleaning products such as oven cleaners and drain cleaners, detergents and paper, as well as aluminum and paper.

Is sodium hydroxide safe to skin?

Concentrated amounts of sodium hydroxide are extremely .caustic, which means it’s corrosive and can cause chemical burns to the skin and eyes. Consuming it or inhaling its fumes can be very dangerous.

Real talk. This makes sodium hydroxide seem pretty scary. However, sodium hydroxide can be added to skin care products in very low doses and is generally exhausted in the reaction process. The harsh effects of the product are eliminated once it touches your skin.

P.S. The FDA generally recognizes sodium hydroxide as safe as an ingredient in food. This is mainly for produce washes and not actual food.

What does sodium hydroxide do in skin care products?

women's assorted cosmetics

Sodium hydroxide is capable of saponifying oils. It helps oils and fats foam up and lather into soap. Your soap wouldn’t be complete without it. It would contain many different oils and fats that don’t all blend together into one product.

It can also be used in small quantities to maintain and establish the pH of products. The pH of skin is usually between 4.5 and 7. This acidity, also known as the “acid mantle”, provides protection against environmental factors such as allergens, pollutant, and bacteria. If your skin care’s pH is out of its typical range, you can disrupt your skin’s acidic protection, which .might .increase your risk of premature aging too.

You’ll find sodium hydroxide most often in the beauty products such as:

  • Soap
  • Makeup
  • Hair dye
  • Nail polish
  • Face wash
  • Body cream
  • Nail polish remover

Side effects of sodium hydroxide on the skin

You should NEVER put pure sodium hydroxide on your skin. It can cause skin symptoms like mild to severe chemical burns, or holes in the skin and underlying tissues. Concentrated amounts of drain and oven cleaners can cause skin damage. Make sure you wear gloves.

The following could be caused by products containing or made with sodium hydroxide

  • Rash
  • Hives
  • Itching
  • Redness or discoloration
  • Itching
  • Flaking skin
  • Increased sensitivity

Using skin care with small concentrations of sodium hydroxide is usually WAY safer. However, you should still be cautious if your skin is sensitive.

Safely using sodium hydroxide products

In small amounts, sodium hydroxide products can be applied topically. Before applying the product, you should do a patch test. Apply a small amount of the product to your ears or forearms. You should not feel any irritation for 24 hours.


Sodium hydroxide, an alkaline compound, is used to balance pH and oily substances. You’ll find it in lots of skin care products like soaps, makeup, cleansers, and lotions.

It can burn your skin if used in high amounts. It’s only used in very small quantities in skin care products, which tend to be completely metabolized in the reaction. So, a lot of it doesn’t actually make it to the final product.

Pure sodium hydroxide is 10/10 hazardous. Ingestion can cause severe breathing difficulties, swelling of the throat, inflammation of the lungs, and throat swelling. If it gets into your eyes, it can cause vision loss.

P.S. Always consult a dermatologist before you make any significant changes to your skin care routine. This is extra important if you have a condition like eczema, psoriasis, cystic acne, or rosacea.