A method of servicing a well is disclosed. The method comprises mixing ingredients to form a well servicing fluid. The ingredients comprise (i) at least one surfactant chosen from alcohol ethoxylates, C4 to C12 primary alcohols and ethoxylated propoxylated alcohols, (ii) a zwitterionic polymer prepared by inverse emulsion polymerization of at least one monomer Ab comprising a betaine group and optionally one or more nonionic monomers Ba, and (iii) a saline based aqueous solution. The well servicing fluid is introduced into a hydrocarbon well.