Image source: Wikipedia.com
Salicylates refers to how the body builds up something until a certain concentration, and then only does the body start reacting on small amounts from then on. An analogy could be something like how a bucket gets filled up with water first and only when it's full that it starts to overflow and cause an effect from then on. Nevertheless, this is just an intolerance, as no antibodies are involved! This could be like a reaction to sulfites (preservatives) in wine.
An interesting fact: people who are allergic to fish are not necessarily allergic to shellfish, and vice versa!
Allergies usually involve proteins. Common symptoms are indigestion, puffiness, discoloration, and swelling. Stay tuned! More on this to come! :)