Is It an Allergy? A Guide to Recognising Reactions to Eyelash Extensions | How to Spot and Manage Allergic Reactions to Lash Extensions 

Imagine this: your client leaves the salon with a stunning set of lashes, only to message you the next day saying, "I think I'm having an allergic reaction!" What should you do next? First, don’t panic – this happens, and it's manageable. Let’s break down how to handle the situation calmly and professionally.

Lash Tech Brushing through client's eyelash extensions

How to Spot an Allergic Reaction to Eyelash Extensions

First things first: is it really an allergic reaction? It’s important to recognise the difference between an allergy and other irritations. A common sign of an allergic reaction is swelling or puffiness around the eyelids. Other symptoms to watch for include:

  • Watery eyes
  • Red or irritated skin around the eyes
  • An itchy lash line
  • Tenderness around the eyelids
  • Allergic reactions can show up in one or both eyes, depending on the person.

If your client’s eyes are bloodshot, though, it’s probably not an allergic reaction. Bloodshot eyes are usually a result of mild chemical irritation. While not pleasant, this issue typically goes away on its own and is easier to prevent in the future. If you want to learn more about chemical burns, check out this blog post! This is an example of a chemical burn:

Lash clients with chemical burns caused by eyelash extension glue

Can You Be Allergic to Eyelash Extensions?

Here’s the good news: clients probably won’t be actually allergic to the eyelash extensions themselves. Today’s eyelash extensions are made from a synthetic material called PBT, which mimics the look of natural hair. Terms like ‘mink’, ‘silk’, or ‘cashmere’ are, these days, used to describe the appearance or texture of different types of lashes, but they’re not the actual cause of allergies.

However, the adhesive used to attach the extensions is a different story. The main ingredient in lash glue is cyanoacrylate, which can trigger allergic reactions in some people. It’s important to note that this ingredient is present in all lash adhesives, even the ones labelled as "sensitive." Occasionally, clients may also have a reaction to the under-eye pads, but that irritation typically goes away shortly after they’re removed. Top tip: Foam Eyepads are an excellent alternative for your more allergy-prone clients.

Reactions to any of the pretreatment products are much less common, as they don’t stay on the skin for long or release any fumes. Still, it’s always good to check if your client has sensitivities to any products that do come into contact with the skin, like lash shampoos or cleansing pads.

Lash glue ingredients on bottle

What Should You Do if Your Client Has an Allergic Reaction?

If your client does experience an allergic reaction, it’s important to advise them to visit their local pharmacist or doctor for professional advice. As a Lash Technician, it’s not within your role to recommend medication or treatment—leave that to the experts! It’s not worth the risk of offering medical advice that could cause further issues.

What you can do is offer to remove the lash extensions if the client wants them off. Just remember that taking the lashes off won’t stop the reaction immediately – the body needs time to settle down.

If your client decides to keep their lashes, that’s fine too. Once the adhesive has fully set and stops emitting fumes, the allergic reaction will usually calm down. However, if your client loves activities like hot yoga, steam rooms, or saunas, it's better to remove the lashes. Why? High heat can soften the glue and release more fumes, which can trigger further irritation.

If your client’s eyes are too swollen to access the lash bonds safely for removal, it’s best to wait for the swelling to reduce before proceeding. Accidentally getting lash remover in a client’s eye is far more unpleasant than waiting for the inflammation to go down, so patience is key!

Removing eyelash extensions

Can Clients Who’ve Had an Allergic Reaction Have Lash Extensions Again?

In most cases, the answer is no. Once a client has developed an allergy to lash glue, future reactions are likely to be worse. Allergic reactions to cyanoacrylate are cumulative, meaning that over time, the body becomes more sensitive to it. This explains why long-term clients can suddenly develop an allergy, even after years of problem-free treatments. Each reaction tends to be stronger than the last, so it's not worth risking another flare-up.

Lash client having an allergic reaction to eyelash extensions

That being said, all is not lost! Our bodies change over time, and it’s possible that after a year or so, your client’s reaction could subside, and they might be able to wear lashes again. But client safety is always the priority, so it’s important to tread carefully if they decide to give lashes another go down the line.