Is Propylene Glycol Safe in Skincare

Friend or Foe? The Truth About Propylene Glycol Safety

If you’ve ever glanced at the ingredients list of your favourite moisturizer, you’ve likely spotted propylene glycol (PG). But wait—isn’t that used in antifreeze? (No!) No wonder the internet is filled with conflicting opinions. Some hail it as a skincare essential, while others warn against it. So, what’s the real story?

As a cosmetic scientist, I know that PG is one of the most misunderstood ingredients in skincare. It’s a safe, effective, and multi-functional component found in thousands of formulations—from serums and creams to cleansers and masks. However, its ability to enhance ingredient absorption means it must be used strategically.

Let’s break down the science, dispel the myths, and determine whether propylene glycol deserves a spot in your skincare routine.

Table Of Contents

Friend or Foe? The Truth About Propylene Glycol Safety
What is Propylene Glycol?
The Science Behind Propylene Glycol’s Skincare Benefits (and Potential Concerns)
Propylene Glycol vs. Other Humectants: How Does It Compare?
Addressing the Myths: Is Propylene Glycol Safe?
Who Should Use Propylene Glycol?
Final Verdict: Should You Use Propylene Glycol?
Key Takeaways

What is Propylene Glycol?

Propylene glycol (PG), also known as 1,2-propanediol, is a colorless, odorless, and water-soluble alcohol that serves multiple functions in skincare:

Humectant – attracts and retains moisture.
Solvent – dissolves active ingredients to improve formulation stability.
Penetration Enhancer – helps beneficial ingredients absorb deeper into the skin.

Unlike its chemical cousin ethylene glycol (which is toxic), PG is FDA-approved, Generally Recognized as Safe (GRAS), and widely used in cosmetics, food, and pharmaceuticals.

Propylene Glycol is FDA-approved, Generally Recognized as Safe (GRAS), and widely used in cosmetics, food, and pharmaceuticals. However, individuals with eczema, rosacea, or a weakened skin barrier may be more vulnerable to sensitivity and irritation from PG-heavy products.

The Science Behind Propylene Glycol’s Skincare Benefits (and Potential Concerns)

1. A Powerful Humectant for Deep Hydration

Much like glycerin, propylene glycol is an excellent humectant, drawing water into the skin to prevent moisture loss. This makes it an essential ingredient in hydrating products like moisturizers, serums, and lotions.

2. Enhancing Ingredient Absorption – A Double-Edged Sword

PG can enhance the penetration of active ingredients such as vitamins, antioxidants, and exfoliating acids. Research has shown that PG can modulate the skin barrier, helping beneficial molecules reach deeper layers. However, this property has some risks:

🔴 Potential Concern: PG doesn’t distinguish between good and bad—it enhances absorption for everything in the formula. If combined with irritants, allergens, or harsh exfoliants, it can increase the risk of irritation, inflammation, and barrier damage.
🔴 Compromised Skin Barrier Risks: Individuals with eczema, rosacea, or a weakened skin barrier may be more vulnerable to sensitivity and irritation from PG-heavy products.

3. Boosting Solubility and Stability

Many potent skincare ingredients, like vitamin C, retinoids, and botanical extracts, are poorly soluble in water. PG acts as a solvent, ensuring these actives remain stable and effective in formulations.

4. Supporting the Skin Barrier & Improving Texture

PG helps support the lipid barrier, protecting against irritation, dryness, and environmental stressors. Additionally, it improves the texture of skincare products, making them feel lightweight and non-greasy. However, excessive use in low-humidity environments can have a paradoxical drying effect.

Propylene Glycol vs. Other Humectants: How Does It Compare?

While propylene glycol is a powerful humectant, it’s not the only one used in skincare. Understanding how it compares to other moisture-binding ingredients is key to making informed choices.

Ingredient	Hydration Power	Penetration Enhancement	Skin Sensitivity
Propylene Glycol	✅ Excellent	✅ Strong	⚠️ May increase irritation if barrier is compromised
Glycerin	✅ Excellent	❌ Low	✅ Very gentle
Hyaluronic Acid	✅ Excellent	❌ Low	✅ Very gentle
Sorbitol	✅ Good	❌ Low	✅ Very gentle

Unlike hyaluronic acid or glycerin, which primarily sit on the skin’s surface, propylene glycol enhances penetration, allowing active ingredients to be delivered deeper into the skin. This can enhance the efficacy of treatments, but it also requires a strategic formulation to prevent unwanted irritation. For those using potent actives, such as retinol or exfoliating acids, the presence of PG should be carefully considered.

Addressing the Myths: Is Propylene Glycol Safe?

1. Does Propylene Glycol Cause Skin Irritation?

Most individuals tolerate PG well, but those with sensitive skin or a compromised barrier should be cautious. The concentration and the formula it’s included in play a crucial role in how it interacts with the skin. If irritation occurs, it’s often due to other factors in the formulation rather than PG itself.

2. Is Propylene Glycol Toxic?

This is one of the biggest misconceptions. Unlike ethylene glycol (which is toxic), PG is FDA-approved and widely recognized as safe by regulatory agencies like the World Health Organization (WHO) and the European Commission. It is water-soluble, does not accumulate in the body, and is safely metabolized.

3. Should You Avoid PG in Skincare?

Avoiding PG entirely may not be necessary unless you have a known allergy or sensitivity. However, if you use highly active skincare ingredients like retinol, AHAs, or fragrance-heavy products, consider how PG might enhance penetration and adjust your routine accordingly. Pairing it with barrier-supporting ingredients like ceramides and niacinamide can help balance its effects.

Who Should Use Propylene Glycol?

Dry & Dehydrated Skin – Retains moisture and prevents transepidermal water loss.

Aging Skin – Enhances penetration of anti-aging actives like retinol and peptides.

Oily & Acne-Prone Skin – Provides lightweight hydration without a greasy feel.

Dull Skin – Aids in delivering brightening ingredients for improved skin texture.

⚠️ Sensitive Skin & Barrier Disorders – Should be combined with barrier-strengthening ingredients to minimize potential irritation.

Final Verdict: Should You Use Propylene Glycol?

Propylene glycol is a science-backed, multi-functional ingredient that enhances skincare formulations in many ways. However, its penetration-enhancing properties require mindful use, those with a compromised skin barrier should proceed with caution.. The key is formulation synergy—pairing PG with soothing, barrier-supporting ingredients can maximise benefits while minimising risks.

Key Takeaways

1️⃣ PG is an effective humectant that can increase ingredient absorption, enhancing both benefits and potential risks.
2️⃣ Formulation matters—combining PG with barrier-supporting ingredients can prevent unwanted irritation.
3️⃣ Those with sensitive skin should patch-test and use PG-containing products alongside ceramides and other skin-strengthening ingredients.

💡 At the core of my cosmetic science philosophy is the belief that skincare should be strategic, science-backed, and personalized. No ingredient is inherently bad—it’s how you use it that makes the difference.

Have you used products with propylene glycol? How has it worked for your skin? Share your experience below!

Talk to you soon!
Dr. Bozica

Is propylene glycol the same as antifreeze?

No. Propylene glycol (PG) is often confused with ethylene glycol, a toxic compound used in industrial antifreeze. PG, on the other hand, is FDA-approved, Generally Recognized as Safe (GRAS), and used in foods, medicines, and skincare. In fact, it’s also added to food products like ice cream and salad dressings to improve texture and moisture retention.

Can propylene glycol irritate sensitive skin?

Yes, in some cases. While most people tolerate PG without issues, individuals with eczema, rosacea, or a compromised barrier may experience stinging, redness, or irritation—especially when PG is combined with strong actives (like acids or retinoids). The risk depends on both the concentration and the full formulation, not just the presence of PG.

Does propylene glycol make other ingredients penetrate too deeply?

It can enhance penetration, which is both beneficial and potentially risky. PG helps vitamins, antioxidants, and peptides reach deeper layers of the skin for improved efficacy. But it doesn’t discriminate—irritants and allergens may also penetrate more easily. That’s why careful formulation and pairing with barrier-supporting ingredients (e.g., ceramides, niacinamide) is key.

Is propylene glycol safer than other humectants like glycerin or hyaluronic acid?

Not “safer,” but different. Glycerin and hyaluronic acid are gentle surface humectants, whereas PG adds the unique benefit of enhancing penetration. This makes PG especially useful in anti-aging or brightening products but less ideal for people with highly sensitive skin. Think of PG as a more potent, multi-functional option rather than a direct substitute.

Should I avoid skincare products with propylene glycol?

Not unless you have a proven allergy or your dermatologist recommends avoiding it. For most skin types, PG-containing products are perfectly safe and effective. If you’re sensitive or using strong actives, balance your routine with soothing, barrier-repair ingredients and always patch-test new formulas.