This is a hot topic in the world of aromatherapy. There are so many different opinions and ideas out there. Blogs cite information that doesn’t sound right. Often it isn’t. So let’s chat about essential oils and allergies, and allergic reactions.
Can You Be Allergic To Essential Oils?
Yes. However, true allergies are rare. First of all, let’s get some basics out of the way. What is an allergy? It is an unnecessary immune reaction to an otherwise harmless substance called an allergen. Many natural substances can be allergens. When the body recognizes the allergen as an invader, it mounts an immune response and signals mast cells to release histamine. This is where symptoms like itchiness, watery eyes, sneezing, hives, rashes, shortness of breath, and anaphylaxis come from.
It is true that essential oils do not contain proteins and proteins are what mount an allergic reaction, however, they can bind to proteins in the skin. This creates a hapten complex, which the immune system can recognize.
However, most essential oil allergies are not IgE-mediated like food allergies. Food allergies are the only type of allergic reaction that involves antibodies. However, essential oils can prime the immune system through T-cells. This is called sensitization.
Types of Allergic Reactions
Type I Reactions result in antibody production, called immunoglobulin E antibodies (IgE). They attach to the mast cell and release histamine. These are reactions to food, drugs, environmental allergens, venom (like a bee sting). Typical results are hay fever symptoms, contact urticaria (hives), anaphylaxis, watery eyes, sneezing. This Type 1 allergic reaction to essential oils is rare, but it can happen.
Those who are allergic to ragweed and get seasonal hay fever symptoms may have a similar reaction to chamomile essential oils. Those who are sensitive to fragrance molecules may also experience mild Type 1 hypersensitivities.
Type II & III reactions involve immunoglobulin G (IgG) and immunoglobulin M (IgM). These are not relevant to essential oils. No reaction has ever been recorded.
Type IV reactions involve T cells in the immune system. These are called delayed hypersensitivity. It may not produce a reaction in the first use but may after subsequent exposure. This is common for things like metals, latex, cosmetics. Repeated exposure will continue to produce a reaction. This is called sensitization as it is priming the immune system to elicit a response and leads to allergic reaction. This usually shows up as dermatitis.
True Allergic Reactions Are Rare
The common symptoms we think of as allergic reactions are rare in essential oil use: anaphylaxis, hives/contact urticaria, hay fever.
There are very few documented cases of anaphylaxis to fragrance molecules and essential oils. Most of them self-reported to a database. Some of them a reaction to an isolated constituent added to a perfume, which isn’t reflective of a true essential oil. Some of them to perfumes themselves, which are manufactured, synthetic ingredients and not a true essential oil. These reactions are possible, but it is rare.
The most common reaction in general is a skin reaction, resulting in redness, itching, and rashes. These are usually caused by undiluted essential oil use. The difference between an irritation and an allergic reaction here is that irritation usually dies down within a few hours whereas allergic reaction may persist for a few days. Extra dilution may lessen any further irritation whereas dilution may not stop an allergic reaction.
The best method to using essential oils is to dilute. This greatly reduces the risk of irritation, and sensitization where delayed immune response occurs after repeated use. Some constituents like menthol, cinnamaldehyde, thymol, eugenol, carvacrol and others are known to irritate the skin, but doesn’t necessarily mean an allergic reaction. Best advice is to heavily dilute these essential oils for topical use.
Individuals with sensitive skin should avoid using essential oils neat on the skin. Essential oils should also be adequately or heavily diluted for babies and children.
Some Essential Oils Actually Improve Allergies
Constituent 1,8-cineole, found in many essential oils but key constituent in eucalyptus and ravintara, was found to reduce production of inflammatory mediators. Alpha-terpineol, also found in ravintsara, has anti-inflammatory effect.
Not only do these essential oils reduce allergic response at the immune level, they are commonly used is to control allergy symptoms.
Is It Actually An Allergy
That leads us to ask this question: you’ve had a skin reaction, does it mean you’re allergic? No. It’s common for essential oils to irritate the skin. That’s why we call for dilution. Sensitivity to a molecule does not necessarily mean allergy. Baking soda is a common skin irritant but having irritated skin from baking soda doesn’t necessarily mean you’re allergic to it.
Essential oils that cause both warm or cool sensations should especially diluted. If you’ve never used essential oils before, don’t jump into neat application on your skin. You don’t know how your body and skin will react. Dilute it first and test it out first.