Abstract: A sealed single-dose break-open package (1) having: a first sheet (2) of semirigid plastic material; a second sheet (3) of flexible plastic material superimposed on and sealed to the first sheet (2) of semirigid plastic material to define a sealed pocket (4) containing a dose of a product (5); and an incision (6) formed in the first sheet (2) of semirigid plastic material to guide controlled breakage of the first sheet (2) along the incision (6) and form an outlet opening for the product (5) through the first sheet (2); the incision (6) varies in depth lengthwise to break the first sheet (2) gradually along the incision (6).