What are the uses of medical glycerin?

Glycerol, chemically known as propanetriol, is a colorless, transparent, odorless, viscous liquid with a sweet taste. It is hygroscopic, combustible, and slightly toxic. Glycerol finds extensive applications in industry, medicine, and daily life, with currently over 1,700 known uses. Based on its purity level, glycerol can be classified into pharmaceutical-grade glycerol and industrial-grade glycerol. Pharmaceutical-grade glycerol, due to its high purity and minimal content of harmful impurities, poses no health risks to humans. Medical glycerol is primarily used to prepare various formulations, solvents, humectants, antifreeze agents, and sweeteners, and is also employed in the manufacture of topical ointments or suppositories.
Be professional! Don't use medical glycerin carelessly.
 
　Medical and skincare products, as the terms themselves suggest, are fundamentally quite different. Yet nowadays, many cosmetic brands are boldly featuring the words “medical” on their packaging and “boosting” the concentration of active ingredients.
 
　Glycerin plus white vinegar for skin itching.

Mix 20 ml of medical glycerin with 80 ml of white vinegar, stir well to create a moisturizing lotion. Immediately apply it all over your body after bathing, while your pores are still fully open and your skin is not yet completely dry, allowing the lotion to deeply penetrate your skin.

This well-known humectant is widely praised for its affordability and excellent value. Although its water-absorbing capacity and long-lasting moisturizing effect are only average, its low price, ease of use, and high safety make it a common ingredient in both low-end and high-end products.

However, there are a few points to note regarding moisturizing here:

1. Dynamic moisturization: After glycerin absorbs moisture, it no longer releases it back into the environment. In contrast, dynamic moisturizers can adjust their moisture-retention capacity based on the surrounding environment. If the skin contains relatively little moisture, the moisturizer will release the absorbed moisture; but if the skin already has sufficient moisture, the moisturizer will stop absorbing more water. Hyaluronic acid and betaine-based moisturizers are both capable of regulating moisture release according to the skin’s hydration levels. This not only ensures effective hydration but also provides a comfortable, balanced feel on the skin.

2. Hydration: Many women talk about “hydrating” their skin. In fact, water isn’t actually absorbed by the skin—instead, it simply evaporates from the skin’s surface. Therefore, the term “hydration” isn’t entirely accurate.

Next, let’s get down to business and talk about the precautions for using glycerin.

1. As mentioned above, glycerin does not have dynamic moisturizing capabilities; therefore, I generally don’t recommend using glycerin in areas with extremely dry climates. In such conditions, glycerin is likely to draw moisture from the skin itself in order to achieve its own equilibrium.

2. If you use only glycerin without a moisturizer, it still won't provide true hydration. The oils in a moisturizer form a film on the skin's surface, preventing moisture from evaporating.

3. The glycerin we usually buy isn't 100% pure—it's a water-based solution diluted with water. This is because 100% glycerin would feel too sticky on the skin.

Using glycerin correctly can achieve the best results with the least amount of money.

1. Toner: A glycerin aqueous solution can serve as a toner, and thanks to glycerin’s excellent safety profile, many women with sensitive skin can use it with confidence. However, for the reasons mentioned earlier, using glycerin alone cannot fully lock in moisture; therefore, after applying glycerin, you should follow up with another layer of moisturizing lotion.

2. Preventing Cracked Hands and Feet: During autumn and winter, many women find their hands and feet prone to cracking. Besides using hand creams, you can also try glycerin. If you add allantoin to the glycerin, the anti-cracking effect will be even better. Usually, I keep a bottle of glycerin in my office so I can rub it on my hands whenever needed, and then apply hand cream in the morning and evening. By doing this, my hands stay wonderfully moisturized throughout the entire winter.

3. Preventing chapped lips: Many women buy lip balms, but actually, glycerin can also be used on the lips—and it’s incredibly effective! Just be careful not to accidentally swallow it, though.

Misconceptions about Glycerin:

1. Causing the face to turn yellow: Glycerin is a pale yellow liquid, but it does not cause the skin to turn yellow.

2. Causing pigmentation: Currently, I haven’t seen any reports indicating that glycerin causes pigmentation.

3. Homemade Glycerin: Some women suggest making glycerin at home. Although it’s easy to prepare an aqueous solution of glycerin, this solution is prone to bacterial growth, so a preservative must be added. For most women, obtaining a preservative can be quite challenging. Therefore, if you decide to make it yourself, you can use a 30% glycerin solution—but it’s best to use small quantities and store the mixture in the refrigerator, using it up as soon as possible to ensure safety.