Gen Professional Collagen is a collagen supplement with a pleasant lemon flavor. Collagen is essential for healthy skin and joints. This formula helps you maintain radiant skin and flexible joints, while enjoying a delicious lemon taste. Composition Collagen. Instructions for use Mix one tablespoon in water or your favorite beverage and take daily. Pharmaceutical advice Collagen is essential for healthy skin and joints. Maintain radiant skin and healthy joints with the delicious lemon flavor of collagen.