I have eaten fish since I was a child with no problems, however a few years ago I ate some fish and this resulted in the feeling of a bone stuck in my throat, though I had eaten no bones. Thinking it was a case of bad fish I ate fish a week later from a different restaurant with the same result. Recently, any intake of fish, however little the portion results in severe chest pains that can last up to a day and usually prevent me from sleeping. I have no other symptoms, I am a healthy 18 year old girl weighing 110 pounds. My only other allergies are eggs and bananas which I was born with. What exactly is causing this reaction to fish? And is there medicine I can take?