We have been talking of eyelash extensions at New York in our previous post here. 
It's of utmost importance that professionals working on the procedure should be well trained and have enough knowledge and equipments to handle individual client requirements. Although rare but allergies from Lash extensions is not unusual.

Your eyes are always shut during the process so the glue used should never enter your eyes, still if it does by any chance it might cause some irritation, depending upon person to person, it might go off naturally, or might cause an allergy. Whatever be the allergic reaction, you will never lose you or sight, all you would need is an appropriate eye drop from your eye doctor. Clients who develop an allergic reaction to their eyelash extension adhesives will typically experience swelling and itching of the eyelids within the first 72 hours of completion of a lash service.

This should be a completely pain free experience, so if you feel any discomfort, make sure you tell your technician. May be just changing the glue will sort it out.

Reactions usually occur when the adhesive is uncured (not dry), developing in response to either the carbon black used to pigment the adhesive or, in more cases, the cyanoacrylate base used in nearly every lash glue on the market. Reactions develop when the glue comes into contact with the skin; the more the glue and the longer a client’s skin is exposed to the adhesive, the higher are the chances of an allergic reaction to occur.
It's not the Lash extension or the fumes of adhesives that cause allergy but attaching the lashes too very close to the skin or the eyeball can be the irritation factor.

Technicians at Las Vegas's Eyelash Extension Training Center PBT, are fully trained to prevent and handle such situations if they occur. We shall talk about prevention and treatment in the next posts.