Proton-binding polymers for oral administration

A method of treating metabolic acidosis in a patient, the method comprising orally administering to the patient a pharmaceutical composition comprising a proton-binding, crosslinked amine polymer comprising the residue of an amine corresponding to Formula 1:

• wherein R1, R2 and R3 are independently hydrogen, hydrocarbyl, substituted hydrocarbyl provided, however, at least one of R1, R2 and R3 is other than hydrogen, the crosslinked amine polymer has an equilibrium swelling ratio in deionized water of less than 2, and the crosslinked amine polymer has an equilibrium proton binding capacity and a chloride binding capacity of at least 5 mmol/g in Simulated Gastric Fluid (“SGF”) containing 35 mM NaCl and 63 mM HCl at pH1.2 and 37° C.