Symptoms of histamine intolerance presents with a wide variety of symptoms such as being prone to headaches, feeling hot, red and itchy at times with flushing of the skin, nasal congestion, sneezing and much more. Symptoms of histamine intolerance can leave you feeling frustrated and not quite sure how to pinpoint the cause as one day you feel fine, the next day you are not as depending on whether you have hit your histamine threshold and your bodies ability to metabolize histamine. ~ Didem