Tylactin RTD 15, Chocolate, 8.3 fl oz., (250 mL). 200 Calories Each. Tylactin RTD 15 Chocolate is for the dietary management of TYR (Tyrosinemia) for individuals over one year of age. Tylactin RTD 15 Chocolate is nutritionally complete, reduced sugar, contains DHA and increased vitamin D, and a nutrient blend designed to support bone health. Tylactin RTD 15 Chocolate is Kosher and Halal Certified.