Blue Dye 1 Allergy Symptoms. Using blue dyes can lead to blue wheals or angioedema and systemic reactions. The most significant known blue 1 side effects is its potential to cause allergic reactions, including skin rashes, hives, or nasal congestion in sensitive individuals.
We have found a cohort of 11 patients with chronic, unexplained pruritic skin disorders that have responded to medication changes centered around avoidance of coloring agents, particularly fd&c blue no. Those who have an intolerance to blue 1 may experience symptoms such as constipation, vomiting, bloating, abdominal discomfort and diarrhea.