However, alcohol denat. is not all that bad.

Due to its low molecular weight, alcohol denat. tends to evaporate quickly. One study on pig skin found half of applied alcohol evaporated in 10 seconds and less than 3% stayed on skin.

This also helps other ingredients become better absorbed upon application.

Studies are conflicted about whether this ingredient causes skin dehydration. One study from 2005 found adding emollients to propanol-based sanitizer decreased skin dryness and irritation. Another study found irritation only occurs if your skin is already damaged.

Small amounts of alcohol are generally tolerated by oily skin or people who live in humid environments.

The rule of thumb is if this alcohol is near the end of an ingredients list, it will probably not affect your skin much.

Also...

This ingredient has antimicrobial and solvent properties.

The antimicrobial property helps preserve products and increase their shelf life. As a solvent, it helps dissolve other ingredients.

Other types of astringent alcohols include:

As a humectant, it helps the skin stay hydrated by pulling moisture to your skin. The low molecular weight of glycerin allows it to pull moisture into the deeper layers of your skin.

Hydrated skin improves your skin barrier; Your skin barrier helps protect against irritants and bacteria.

Glycerin has also been found to have antimicrobial and antiviral properties. Due to these properties, glycerin is often used in wound and burn treatments.

In cosmetics, glycerin is usually derived from plants such as soybean or palm. However, it can also be sourced from animals, such as tallow or animal fat.

This ingredient is organic, colorless, odorless, and non-toxic.

Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.

Like hydroquinone, this ingredient helps with treating hyperpigmentation. In fact, studies show it works better than traditional hydroquinone.

Thiamidol is a potent tyrosinase inhibitor, meaning it blocks tyrosinase. Tyrosinase is the enzyme used by our bodies to create melanin.

A quick refresher: melanin gives our skin, hair, and eyes pigment or color. Skin exposed to UV will create melanin as a way to protect itself, AKA tanning.

Studies show thiamidol didn't induce the familiar side effects of hydroquinone: redness, itchiness, dryness, and worsening discoloration.

A study from Beiersdorf about the Eucerin Anti-Pigment Dual serum showed hyperpigmentation was reduced up to 75% after 12 weeks of continuous use.