[header] How to live with an allergy to shellfish [title] Read labels. [step] Manufacturers are not required to note it on the label if they have shellfish in them, though many of them do. In addition, items are usually not labelled for shellfish if they contain mollusks such as clams, scallops, or oysters. 
Therefore, it's always best to read the label. [substeps] It's important to check all labels.