Ingredient review

SD Alcohol 23-H

INCI: SD ALCOHOL 23-H

SD Alcohol 23-H is a fast-evaporating solvent that can help products feel lightweight but may dry or irritate sensitive skin.

beautyskincaresolvent

In plain English

SD Alcohol 23-H is a type of denatured alcohol—ethanol that has been made undrinkable by adding bitter or toxic compounds. In skincare, it helps ingredients dissolve, makes products feel light and quick-drying, and can temporarily tighten pores. However, it can strip the skin's natural oils, leading to dryness or irritation, especially for sensitive or dry skin types.

Quick decision guide

Useful, but context matters

SD Alcohol 23-H 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-H.
  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-H is a denatured alcohol, meaning ethanol (grain alcohol) mixed with denaturants to make it unsuitable for consumption. It is commonly used in cosmetics as a solvent and antimicrobial agent.

How it works

It evaporates quickly from the skin, carrying away excess oil and helping other ingredients penetrate. Its antimicrobial properties can reduce surface bacteria, which is why it appears in acne products. However, rapid evaporation can also strip the skin's moisture barrier.

Pros

Quick evaporation

Products dry fast, leaving a non-sticky, matte finish—ideal for oily skin or humid climates.

Antimicrobial benefits

Helps reduce surface bacteria, which can be beneficial for acne-prone skin when used in moderation.

Cons and cautions

Drying effect

Repeated use can strip natural oils, leading to tightness, flaking, and increased sensitivity over time.

Irritation risk

High concentrations or frequent application can cause redness, stinging, and barrier damage, especially on sensitive skin.

Best for

  • People with oily or acne-prone skin who tolerate alcohol well
  • Those looking for a fast-drying toner or astringent

Use caution if

  • People with dry, sensitive, or eczema-prone skin
  • Those with a compromised skin barrier or rosacea

Usage tips

Use only on oily or acne-prone areas, not all over the face.
Follow with a hydrating moisturizer to replenish moisture lost from alcohol evaporation.
Avoid using multiple alcohol-based products in the same routine.

Safety summary

SD Alcohol 23-H is safe in regulated concentrations but can cause dryness and irritation with overuse. It is not recommended for sensitive or dry skin types. 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) when used repeatedly. However, low concentrations in rinse-off products are generally well-tolerated.

Common label clues

Typical concentration
1% to 50% depending on product type; lower in leave-on products, higher in rinses
Regulatory status
Approved for use in cosmetics in the US (FDA) and EU (CosIng) with concentration limits for leave-on products.
Common uses
Toners, Astringents, Cleansers, Acne treatments, Hair styling products
Environmental note
Denatured alcohol is produced from ethanol, which can be derived from corn or sugarcane. Its production has a moderate carbon footprint, but it is biodegradable.

Good to know

  • SD Alcohol 23-H is similar to SD Alcohol 40-B but uses a different denaturing formula.
  • In the EU, denatured alcohol is often listed as 'Alcohol Denat.' on labels.
  • Not all alcohols in skincare are drying—fatty alcohols like cetyl alcohol are moisturizing.

Common questions

What is SD Alcohol 23-H in beauty products?

SD Alcohol 23-H is a type of denatured alcohol—ethanol that has been made undrinkable by adding bitter or toxic compounds. In skincare, it helps ingredients dissolve, makes products feel light and quick-drying, and can temporarily tighten pores. However, it can strip the skin's natural oils, leading to dryness or irritation, especially for sensitive or dry skin types.

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

It evaporates quickly from the skin, carrying away excess oil and helping other ingredients penetrate. Its antimicrobial properties can reduce surface bacteria, which is why it appears in acne products. However, rapid evaporation can also strip the skin's moisture barrier.

Is SD Alcohol 23-H safe for most people?

SD Alcohol 23-H is safe in regulated concentrations but can cause dryness and irritation with overuse. It is not recommended for sensitive or dry skin types. Avoid contact with eyes and broken skin.

Who should be careful with SD Alcohol 23-H?

People with dry, sensitive, or eczema-prone skin Those with a compromised skin barrier or rosacea

Research sources

FDA: Denatured Alcohol in CosmeticsOpenCosIng Database - Alcohol Denat.OpenPubMed: Effects of Alcohol on 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.