The invention provides a dry composition for admixture with water, wherein the composition is optionally presented in two or more parts and comprises, per litre of solution to be made, the following components: (a) 85 to 115 g polyethylene glycol (PEG) having an average molecular weight of 2500 to 4500; (b) 6 to 9 g sodium sulfate; (c) 2 to 3 g sodium chloride; (d) 0.5 to 1.5 g potassium chloride; (e) 5 to 15 g of an organic acid component; and (f) orange flavouring. Also provided are solutions, kits, unit doses and methods that comprise use the compositions.