Nasacort Allergy Nasal Spray is a type of medication that is designed to provide relief for the effects of allergies, such as hay fever. The active ingredient in this nasal spray is triamcinolone acetonide, which is a member of a group of medicines known as corticosteroids. This means that it is a steroid, and will relieve allergy symptoms such as sneezing, itchiness, and a blocked or runny nose. It works by spraying directly into the nose.