How Keratolytics Can Help With Skin Conditions

Keratolytics are medications designed to dissolve skin flakes and scales. Removing these scales not only improves the appearance of the skin and minimizes dandruff but can also help other topical medications to penetrate the skin better.

Keratolytics work by softening keratin, a tough, protective protein produced by skin cells called keratinocytes that make up the majority of the structure of the skin.

Keratolytic agents can be found in medicated shampoos, topical ointments, and skin creams and lotions. They can help treat dandruff as well as skin conditions like calluses, acne, and psoriasis.

This article describes the different types of keratolytic agents and the conditions they can help treat. It also explains possible side effects and when it is time to seek medical care.

Types of Keratolytics

Keratolytic agents commonly used in skin care products include salicylic acid, urea, lactic acid, coal tar, and olive oil. These can be found in many over-the-counter (OTC) products.

There are keratolytic agents like acitretin, tazarotene, and tretinoin (not covered in this article) that are available by prescription only.

Salicylic Acid

Salicylic acid is a keratolytic agent naturally in willow bark and wintergreen leaves but can also be manufactured in the lab. Salicylic acid works by breaking down hydrogen bonds between living and dead skin cells, much like an exfoliant.

It is used to treat common skin conditions such as:

• Acne
• Dandruff
• Psoriasis
• Seborrheic dermatitis
• Calluses
• Corns
• Common warts
• Plantar warts
  

Medicated creams and lotions with 5% or 10% salicylic acid 5% are used for acne and psoriasis. As much as 40% salicylic acid may be needed to treat warts and corns.

By breaking down the skin barrier, salicylic acid allows other agents to penetrate the skin more easily. Salicylic acid should not be overused or applied to broken skin as this can cause redness, irritation, or pain.

Urea

Urea is an organic compound commonly used in skin care products to soften and soothe the skin. It has hydrating and anti-itch properties and also helps other medications penetrate the skin. Urea found in skin care products is synthetic and not animal-derived.

Urea can help treat many skin conditions, including:

• Eczema (atopic dermatitis)
• Ichthyosis
• Xerosis
• Hyperkeratosis
• Actinic keratosis ("sun spots")
• Seborrheic dermatitis
• Psoriasis
• Tinea pedis (athlete's foot)

Urea works similarly to salicylic acid but also locks moisture into the coarse outer layer of skin cells called the stratum corneum. It also has antibacterial properties.

Urea is generally regarded as safe and can be used in concentrations as high as 50%. Some people may experience a burning or stinging sensation, but this is rare.

Lactic Acid

Lactic acid is a type of acid produced by the body during metabolism that has keratolytic properties. The type used in skin care products is derived from milk.

In addition to exfoliating the skin, lactic acid helps stimulate skin cell renewal and keep the skin hydrated. It is often promoted for its "anti-aging" properties. At higher concentrations, lactic acid can be used by cosmetic dermatologists for chemical skin peels.

Lactic acid is often used to treat skin conditions like:

• Psoriasis
• Keratosis pilaris
• Rosacea
• Photoaging (sun-damaged skin)

Over-the-counter creams and lotions containing 5% lactic acid can help make the skin look smoother, while 12% lactic acid formulation can penetrate deeper layers and promote skin cell regeneration.

Lactic acid should not be overused as it can cause irritation and redness. It can also make your skin more sensitive to the sun.

Coal Tar

Coal tar is a centuries-old remedy for psoriasis that is still used to treat this and other skin conditions. It is the byproduct of coal and is included on the World Health Organization's List of Essential Medicines.

In addition to being a keratolytic agent, coal tar has potent anti-inflammatory properties that make it useful for treating inflammatory skin condtions.

Coal tar is commonly used to treat:

• Dandruff
• Eczema
• Psoriasis
• Seborrheic dermatitis

Coal tar products were traditionally black or gray but today are largely decolorized. Even so, they can still stain clothing and temporarily discolor blond or bleached hair. Coal tar is generally safe to use but can cause itching and irritation in some people.

Avoid prolonged sun exposure 72 hours after application as coal tar can make your skin extra sensitive to ultraviolet (UV) rays.

Olive Oil

Olive oil is another centuries-old skin treatment with keratolytic, anti-inflammatory, and hydrating properties.

These effects are attributed to plant-based phenolic acids called hydroxytyrosol, tyrosol, and oleocanthal. These compounds not only break hydrogen bonds in the same way as salicylic acid and urea but also break molecular bonds that neutralize free radicals that cause skin aging.

Olive oil has been used to treat conditions like:

• Eczema
• Psoriasis
• Actinic keratosis
• Seborrheic dermatitis (including "cradle cap" in babies)
• Diaper dermatitis (diaper rash)
• Cracked nipples

Some people believe that olive oil can speed wound healing, but there is little evidence to support the claim.

Olive oil is generally safe for use but may clog pores, contributing to acne. It should be used with caution on sensitive skin.

Skin Conditions Keratolytics Treat

Keratolytics are helpful in treating a number of skin conditions, including common skin troubles such as dandruff, acne, and calluses. A few of the conditions keratolytics can help with are outlined below.

Dandruff

Dandruff is a symptom of a condition known as seborrheic dermatitis. Marked by red, greasy skin covered with flaky, white or yellow scales, seborrheic dermatitis often affects the scalp, but can also show up in other areas that are rich in oil glands, such as your eyebrows, the sides of your nose, and groin area.

Salicylic acid is a common ingredient in dandruff shampoos that you can buy over the counter. Well-known dandruff shampoos that use salicylic acid include Selsun Blue and T/Sal by Neutrogena.

Acne

Acne, the blemishes that show up during nearly everyone's teenage years, is another common skin condition that keratolytics can help with.

Shedding skin, overactive oil glands, or an overgrowth of bacteria clog up pores of the skin, causing acne. Salicylic acid eases inflammation and unclogs pores, helping to clear up acne-prone skin.

You can find over-the-counter salicylic acid treatments in strengths of 0.5% to 2% as topical gels and creams.

Calluses

Calluses is the buildup of hard, thickened skin caused by repeated rubbing or constant pressure on the skin. Typically, calluses show up on the bottoms of the feet and palms of the hands.

As softening and emollient agents, salicylic acid and urea can help with calluses. Look for creams or lotions that have these keratolytics in them.

Psoriasis

Psoriasis is a chronic condition in which the immune system causes the body to make skin cells too quickly. The extra cells pile up, leading to visible patches of thick, silvery scales that tend to itch.

Salicylic acid, urea, and lactic acid keratolytics can all help relieve symptoms of psoriasis. The salicylic acid will help to reduce inflammation, while urea and lactic acid will help to soften and remove the scales.

Be sure to follow the directions as indicated when using a medication containing salicylic acid, as too much can make psoriasis symptoms worse.

Keratosis Pilaris

Keratosis pilaris is a harmless skin condition that looks like tiny bumps. The bumps can be red or white and are sometimes described as little pimples or chicken skin. They show up because dead skin cells are clogging up pores on the skin where hair grows.

Keratosis pilaris doesn't need to be treated, but it can make your skin feel dry and itchy. Moisturizers and lotions that contain urea and lactic acid, such as AmLactin and Urix40, can help relieve these symptoms.

You can also gently exfoliate the area, such as with a loofah or washcloth, or use a cream like Salex lotion that contains salicylic acid. The salicylic acid will help to slough away dead skin cells.

Side Effects of Keratolytics

Keratolytics can cause side effects, the severity of which can differ based on the agent, formulation, and concentration. Side effects are usually mild and include:

• Reddening of the skin
• A burning or tingling sensation
• Itchiness
• Sensitivity to UV light

Summary

Keratolytic agents help remove skin scales to make the skin smoother. They are often used to help treat conditions like dandruff, psoriasis, eczema, seborrheic dermatitis, and actinic keratosis. They are available in skin ointments, lotions, and creams as well as shampoos.

Keratolytic agents used in these products include salicylic acid, urea, lactic acid, coal tar, and olive oil. Keratolytic agents are generally safe for use but may cause mild redness, itching, and UV light sensitivity in some people.