TCP Antiseptic Liquid TCP Antiseptic Liquid provides symptomatic relief of sore throats including those associated with colds & flu. It can also be used for common mouth ulcers, cuts, grazes, bites & stings, boils, spots & pimples. Ingredients Active ingredients: Phenol (0.175% w/v) & halogenated phenols (0.68% w/v). Other ingredients: Glycerol, concentrated phosphoric acid, quinoline yellow (E104) & purified water. Directions For Sore Throats: Gargle twice daily diluted 1:5 in water. Mouth Ulcer: Apply undiluted 3 times a day. Spots: Apply undiluted 4 hourly. Cuts: Apply diluted 1:1 with water.