I am allergic to crustaceans.
kros-TAH-cheh-ee — four syllables, stress on second. The 'cei' = 'cheh-ee', two separate sounds.
Use in seafood restaurants or when 'frutti di mare' is on the menu. Crustaceans include shrimp, prawns, crab, and lobster — all featured prominently in Italian coastal cuisine.
'Ai crostacei' = 'a + i + crostacei'. Crustaceans (crostacei) are a separate allergen category from mollusks (molluschi) in EU law. People allergic to one may tolerate the other, so specifying is important.
Sono allergico ai gamberi.
I am allergic to shrimp/prawns.
More specific — gamberi are the most common crustacean in Italian menus.
Niente gamberi, grazie.
No shrimp, thank you.
Simple exclusion for milder sensitivity.
L'antipasto contiene gamberi?
Does the appetizer contain shrimp?
Checking a specific dish.
Italian seafood menus can be complex. 'Frutti di mare' (fruits of the sea) typically includes both crustaceans and mollusks mixed together. Always ask for detailed ingredient lists in seafood restaurants.