Irritation: “discomfort in a body part caused by a reaction to an irritant substance.”
There are several things that can cause an irritation pre and post appointment
Inflammation: “your body's process of fighting against things that harm it, such as infections, injuries, and toxins, in an attempt to heal itself”
Allergies: “A condition in which the immune system reacts abnormally to a foreign substance.”
Allergic Reaction: “The hypersensitive response of the immune system of an allergic individual to a substance..”
Some of these issues can be easily relieved with eye drops and anti-histamine products. I am by no means a doctor of any kind so please consult a doctor and make sure that using these products are ok for you. Although most of these are minor issues, if you are unsure and the condition becomes exceptionally uncomfortable and unbearable, please do not brush it off and seek medical attention immediately.