Ingredient review

SD Alcohol 23-A

INCI: SD ALCOHOL 23-A

SD Alcohol 23-A is a fast-evaporating solvent that can help products feel lightweight but may be drying or irritating for some skin types.

beautyskincaresolvent

In plain English

SD Alcohol 23-A is a type of denatured alcohol—ethanol that has been made undrinkable by adding other chemicals. In skincare, it helps ingredients dissolve, makes products feel light and quick-drying, and can kill bacteria. However, it can strip the skin's natural oils and disrupt the moisture barrier, especially with frequent use on dry or sensitive skin.

Review score

Safety, usefulness, and evidence

3.5Good
3.5/ 5

Potentially useful with some tradeoffs

The evidence base is relatively strong for its common cosmetic role.

Main practical flags: irritation is moderate; clogging risk is low.

Source
synthetic
Evidence
strong
Irritation
moderate
Clogging risk
low
How reviews are scored

Quick decision guide

Useful, but context matters

SD Alcohol 23-A can be useful, but watch for some irritation potential.

Plain-English read

Treat this as a practical screening step before you compare products that contain this ingredient.

  1. Step 1Start with the score, then check the irritation and clogging risk before judging SD Alcohol 23-A.
  2. Step 2Use the "Best for" and "Use caution if" sections to match the ingredient to your skin, not just to a marketing claim.
  3. Step 3If a product stings, breaks you out, or worsens irritation, judge the finished formula and stop using it even if the ingredient scores well.

Score terms in plain English

Irritation risk

moderate

Can bother some users, especially with frequent use, damaged skin, or strong companion ingredients.

Clogging risk

low

Less likely to feel heavy or contribute to clogged pores for most skin types.

Evidence level

strong

There is a stronger practical or research basis for the ingredient role described here.

What it is

SD Alcohol 23-A is a denatured alcohol (ethanol) used in cosmetics as a solvent, antimicrobial, and astringent. It evaporates quickly, leaving a dry feel.

How it works

It dissolves oil-soluble and water-soluble ingredients, helps products spread evenly, and evaporates rapidly to create a cooling, matte finish. Its antimicrobial properties can help preserve formulas and reduce surface bacteria.

Pros

Fast evaporation

Leaves skin feeling dry and matte, ideal for oily skin types who dislike heavy or sticky textures.

Antimicrobial action

Helps reduce surface bacteria and can improve product preservation, reducing the need for other preservatives.

Cons and cautions

Drying effect

Can strip natural oils and moisture, leading to tightness, flakiness, or irritation, especially with frequent use.

Barrier disruption

Repeated use may weaken the skin's protective barrier, increasing sensitivity and water loss over time.

Best for

  • Oily or acne-prone skin looking for a matte finish
  • Those who tolerate alcohol well and want fast-absorbing products

Use caution if

  • Dry, dehydrated, or sensitive skin
  • Those with compromised skin barrier or conditions like eczema or rosacea

Usage tips

Use only on oily or acne-prone areas, not all over the face.
Follow with a moisturizer to replenish hydration after using alcohol-based products.
Avoid using high-alcohol products more than once daily.

Safety summary

SD Alcohol 23-A is generally safe in cosmetics at typical concentrations, but can cause dryness and irritation, especially for sensitive or dry skin. Avoid contact with eyes and broken skin.

Research notes

Studies confirm that denatured alcohol can disrupt the skin barrier and increase transepidermal water loss (TEWL) with repeated use. However, it is effective as a solvent and antimicrobial in well-formulated products.

Common label clues

Typical concentration
1-50% depending on product type
Regulatory status
Approved for use in cosmetics in the US (FDA) and EU (CosIng) with concentration limits. Not for oral consumption.
Common uses
Toners, Cleansers, Astringents, Fragrance
Environmental note
Produced from fermentation of crops or petrochemicals; biodegradable but energy-intensive to produce.

Good to know

  • SD Alcohol 23-A is one of several denatured alcohol variants; the number indicates the denaturing formula used.
  • In the EU, denatured alcohol is often listed as Alcohol Denat. on labels.

Common questions

What is SD Alcohol 23-A in beauty products?

SD Alcohol 23-A is a type of denatured alcohol—ethanol that has been made undrinkable by adding other chemicals. In skincare, it helps ingredients dissolve, makes products feel light and quick-drying, and can kill bacteria. However, it can strip the skin's natural oils and disrupt the moisture barrier, especially with frequent use on dry or sensitive skin.

What does SD Alcohol 23-A do in a beauty product?

It dissolves oil-soluble and water-soluble ingredients, helps products spread evenly, and evaporates rapidly to create a cooling, matte finish. Its antimicrobial properties can help preserve formulas and reduce surface bacteria.

Is SD Alcohol 23-A safe for most people?

SD Alcohol 23-A is generally safe in cosmetics at typical concentrations, but can cause dryness and irritation, especially for sensitive or dry skin. Avoid contact with eyes and broken skin.

Who should be careful with SD Alcohol 23-A?

Dry, dehydrated, or sensitive skin Those with compromised skin barrier or conditions like eczema or rosacea

Research sources

FDA - Denatured AlcoholOpenCosIng - Alcohol Denat.OpenPubMed - Alcohol and Skin BarrierOpen

Ingredient reviews are educational and are not medical advice. Patch test new products and ask a licensed clinician about persistent irritation, allergies, pregnancy-specific questions, or diagnosed skin conditions.