DURO-TUSS RELIEF Cough, Cold & Flu Liquid is a herbal formulation. Sambucus nigra (Elder flower) has been traditionally used in Western herbal medicine to help relieve common cold and flu symptoms, such as a cough, sore throat, nasal congestion and runny nose. Althaea officinalis (Marshmallow) has been traditionally used in Western herbal medicine to help relieve throat irritation and an associated dry, unproductive cough. and help relieve throat irritation and associated dry cough. No added sugar. Free from: artificial colours, gluten and lactose. Take back control of your cough No added sugar FREE FROM: Artificial colours, gluten and lactose Non-drowsy Great taste Free from: artificial colours, gluten and lactose.