A physician will conduct a physical examination of the patient as well as compile a medical history and a list of symptoms.

If vernal conjunctivitis is suspected, scrapings of the conjunctiva may be performed. This usually will reveal elevated levels of activated T cells (a white blood cell involved in many immune system functions), eosinophils (a white blood cell involved in allergic reactions) and mast cells (cells involved in the creation of histamine during allergic reactions). In addition, tears from patients with vernal conjunctivitis often contain high levels of leukotrienes and histamine, which are chemicals that trigger symptoms during an allergic reaction.

Allergens that come into contact with the eye are believed to trigger vernal conjunctivitis. For this reason, patients may undergo allergy testing to determine the source of an allergic reaction. The most common method of identifying allergens is skin testing.

The key to treating vernal conjunctivitis is to prevent eyesight damage by making sure the condition does not affect the cornea. Low-dose corticosteroid eye drops are often prescribed to reduce inflammation and keep the cornea from being damaged. These must be used according to a physician’s orders, as overuse of corticosteroid eye drops can result in cataracts (clouding of the eye lens) and/or glaucoma (a group of diseases that occur when the normal fluid pressure inside the eyes slowly rises). They also increase the patient's risk for eye infection.

Mast cell stabilizer/antihistamine eye drops may be prescribed to treat the intense itching often associated with vernal conjunctivitis. Allergy shots (immunotherapy) may also be considered for the long-term treatment of vernal conjunctivitis.

Patients should be careful not to rub their eyes, as this will only irritate them and make symptoms worse. They may find relief from symptoms by using cold compresses, which are cloths or rags soaked in cold water and placed over the eyes.

In addition, patients should take steps to avoid or limit their contact with the allergens that trigger their symptoms.