Where is a patch test performed for lash glue?

• A. On the palm
• B. On the neck
• C. Behind the ear
• D. On the eyelid

Answer: (C)

Patch testing lash glue checks for an allergy to the adhesive, usually a cyanoacrylate-based product, by placing a tiny amount on the skin and watching for redness, itching, or swelling over 24 to 72 hours. The preferred site is behind the ear because the skin there is thin and sensitive enough to reveal reactions, yet protected and easy to monitor without rubbing or contact with the eyes. This location provides a reliable indication of how the glue might affect the client in real use while minimizing risk. Testing on the eyelid is too risky and could cause irritation in a very sensitive area, and the palm or neck are not as representative of how the adhesive will interact with the eyelid skin.