Allergy to shellfish is caused by proteins?

Yes. Most allergens are proteins. A few are carbohydrates. Tropomyosin is one of the possible allergens in shrimp, for example. It is a muscle protein.

Related Questions

Red krill oil capsules: apart from allergy to shellfish what other things in it that can cause a reaction?

Gelatin. Several products available, but most have: krill oil, omega-3 fatty acids, epa (eicosapentaenoic acid), dha (docosahaxaenoic acid), gelatin , glycerin , sorbitol , water , and vanillin. A small proportion of people are allergic to gelatin. The rest of those ingredients are not considered harmful or risky for persons with allergies. Read more...