Propylene glycol (PG) is one of the world’s most commonly used chemicals, so it is extremely unfortunate that some people are allergic to it. In one study published in a German medical journal in 1982, a total of 84 volunteers were tested for a potential PG allergy with a skin patch test using 100-percent PG. Of those, five volunteers (5.95 percent) experienced allergic reactions. Seven additional volunteers experienced skin irritation. Those are fairly significant numbers, and for that reason, you might be worried about whether it’s safe to vape if you’re allergic or sensitive to PG.
This article is not medical advice. If you think that you may have an allergy to propylene glycol or anything else, the only way to find out for sure is by consulting with your doctor and having the appropriate tests performed. It is our hope, however, that this article will shed light on the subject by explaining PG allergies and sensitivities as they pertain to vaping.
What Is Propylene Glycol, and What Are Its Uses?
Propylene glycol is a synthetic chemical with a molecular structure similar to that of alcohol. It is clear, has no scent and tastes slightly sweet. It is viscous and feels slightly oily between the fingers. PG has received the Generally Recognized as Safe (GRAS) classification from the United States Food and Drug Administration and is therefore approved for use as a food additive.
The Uses of Propylene Glycol
PG has a wide array of useful properties. For that reason, it is used in an enormous variety of consumer products. Here are just a few of them.
- PG absorbs and traps moisture, so it’s used in lotions and eyedrops. It can also help to prevent shelf-stable foods from going stale.
- PG emulsifies in the ingredients in a liquid. Used in beverages, medications and beauty products, it prevents the ingredients in those products from separating.
- PG is slightly sweet, so it can augment sugar or sugar substitutes in foods or beverages.
- PG is a solvent that can be used as a carrier for flavors, scents and medications.
- PG creates a visible cloud when it’s heated, which is one reason why it’s used in e-cigarettes. It’s also used in smoke machines.
Propylene Glycol is the Perfect Base for E-Liquid
As you’ve probably surmised from reading the list above, the properties of PG make it ideal for use as a base for e-cigarette fluid. People who vape want to see clouds, because that’s what lets them know that they’re “smoking.” PG is perfect for that. It also dilutes the flavors and nicotine used to create e-liquid, which is necessary because those ingredients are very concentrated in their commercial forms. Even PG’s ability to emulsify ingredients makes it useful for e-liquid because it allows the fluid’s many ingredients to remain evenly distributed throughout the bottle.
How to Identify a Possible Propylene Glycol Allergy
Research suggests that if you are allergic or sensitive to propylene glycol, you’ll most likely experience a skin reaction. Some of the most common reactions include:
- Itching, burning, dry or flaky skin.
- Red rash, bumps, swelling or itching in the area that has come into contact with PG.
- Severe throat irritation or coughing if you vape.
If you vape or are considering vaping, it may be helpful to learn more about the side effects of vaping. If you do experience anything unusual during your switch from smoking to vaping, knowing the typical side effects can help you understand whether what you’re experiencing is an allergic reaction or simply a normal consequence of quitting smoking.
How to Vape If You’re Allergic to Propylene Glycol
If you’re thinking about switching to vaping and are nervous about the possibility that you might be allergic to propylene glycol, you might have read the “5.95 percent” figure at the top of this article and felt a little nervous about it. The fact is, however, that it’s virtually impossible for there to be a 5.95-percent chance of experiencing an allergic reaction from vaping. PG is in almost all e-liquids. If more than one in 20 people experienced allergic reactions when vaping, e-cigarettes never would have become the mainstream consumer products that they are today.
You Probably Don’t Have a Propylene Glycol Allergy
Unless you’ve had a test result confirming that you’re allergic to PG, you can most likely switch to vaping without worrying that you’ll experience an allergic reaction. As you’ve learned from reading this article, PG is in so many products that you ingest or put on your skin that it would be very difficult for you to have a PG allergy and not know about it already.
Propylene Glycol Is a Common Tobacco Additive
Another thing to keep in mind is that PG is an ingredient in many tobacco products. You’ll find PG in varying amounts in cigarettes, pipe tobacco and smokeless products like chewing tobacco and snus. It’s also used in heat-not-burn cigarettes like IQOS because it helps those products create clouds. The main purpose of PG in tobacco products is to keep those products from drying out. Without the PG, you’d have to keep all tobacco products in humidors – not just cigars. So, if you smoke, you’re most likely inhaling PG already.
Of course, there’s a big difference in the concentration of PG in tobacco products compared to e-liquid – so there’s still a minute chance that you might experience coughing, throat irritation or dermatitis symptoms around your mouth when you switch to vaping, exposing a PG allergy or sensitivity that you never knew you had. If that’s the case, you can avoid those symptoms by choosing your e-liquid carefully.
How to Vape If You have a Propylene Glycol Allergy
The most important thing to know about vaping if you’re allergic to propylene glycol is that it isn’t necessary to come into contact with propylene glycol at all if you vape. PG isn’t the only base liquid that’s available for e-liquid; vegetable glycerin is also very common. Most of the e-liquids currently on the market use blends of VG and PG, and some of those “blends” actually include no PG at all. You simply need to look for an e-liquid that’s advertised as using 100-percent VG.
When buying e-liquid, you should be aware that the terms “Max VG” and “High VG” have no universally accepted definition. A “Max VG” e-liquid may still contain PG, either to prevent the mixture from being too viscous or because the e-liquid includes PG-based flavors. An e-liquid labeled “100-percent VG” should contain no PG at all. If you have a true PG allergy, though, it may be worthwhile to contact the manufacturer of an e-liquid before buying it. If the manufacturer uses no PG-based flavors, you should be completely safe using that e-liquid.