A Patch Testing Guide to Henna Brows

Arguably the most crucial part of your brow appointments… patch testing! Everyone’s heard of a patch test but unfortunately, many brow artists try and get away with not doing one. We see a lot of people trying to skip this step however, it is SO important that you complete it and are thorough. Let's dive into how to patch test for henna brows and why you should do it without fail!

An image of a pot of So Henna brow henna

Why Should You Patch Test Henna Brows? 

Whilst brow henna is a mostly natural product and is derived from plants, there is always still a chance of an allergic reaction, as everyone’s skin is completely unique which is why it’s impossible to predict. Our So Henna brow mix also contains very small amounts of PPD which is the same chemical found in traditional brow and hair dyes and has the potential to cause a reaction.

With henna powder being applied to the face and very close to their eyes, it’s very important that any allergies or irritations are discovered beforehand on a less sensitive area. 

Another reason to patch test (which is often overlooked), is that the manufacturer says so! Okay… why does that matter so much? If the manufacturer of your brow henna brand states that you must patch-test the product, then it is unlikely that your insurance will cover you if you don’t. If your client does have an allergic reaction and sues you and you didn’t patch test when it was recommended you do, then your insurance will probably be void and then you’ll be in deep water. Always check with your insurance company and manufacturer suggestions if a patch test is required before booking a client in.

When Should You Do a Brow Henna Patch Test?

You should patch test every new henna brows client at least 48 hours before their brow appointment. This will allow enough time for any sensitivities or allergies to show up prior to the booking.

At So Henna, we also recommend completing a patch test on your clients every six months, as a brow henna allergy can be cumulative. This means that whilst they may not react the first time you do their brows, they may do after multiple treatments as our skin can change and people can react to things they weren’t previously allergic to. This practice covers your back and also ensures you are prioritising the safety of your customers at all times. 

How To Do a Brow Henna Patch Test

To do a patch test, simply apply a small amount of product behind the ear and request that your client leaves it alone for 48 hours, letting you know if they notice any redness, itching, swelling or adverse reactions prior to their treatment. 

We always recommend applying each of the products you will be using during the treatment to make sure you cover all bases. If you patch-tested for the brow henna but not the brow oil, for example, there is still a risk of reaction.



Completing a patch test can seem like a lot of effort, but it’s extremely important and should not be skipped. It’s always better to be safe than sorry, and it’s never worth risking your business or your client’s safety over a quick patch test. If you have any questions on this topic, don’t hesitate to reach out to us on Instagram @sohenna_official or just click the chat icon below!