However, no studies have been done in humans that specifically address this question, so the use of CosaminDS during pregnancy should be an individual decision made by the patient after consultation with her physician. Sulfa drugs are characterized by having a benzene ring and a sulfanilamide group as part of their molecular structure. People who are allergic to sulfa drugs are probably reacting to their characteristic molecular structure. The compounds in CosaminDS do not have similar molecular structures. An allergy to sulfa drugs should not be interpreted as an allergy to sulfur.
Sulfur is an essential element that is present in many foods and occurs in every cell in the body.
People who are allergic to shellfish are actually reacting to proteins that are present in the shellfish, but not in other foods. Glucosamine is extracted from chitin that make up the shells of crabs and similiar shellfish. Some glucosamine products may also contain impurities, like proteins, which could cause allergic reactions. Because it contains no iodine, no shelfish protein, and no heavy metals, Cosamin is extremely unlikely to cause an allergic reaction.