Methods and compositions for treatment of ion imbalances

1. A method of removing sodium from an animal subject comprising administering to an animal subject in need thereof an effective amount of a core-shell composition comprising a cation exchange core and a semi-permeable shell wherein the semi-permeable shell comprises a polymer containing at least one of a poly-11 trimethylammonioundecylmethacrylate polymer, or a 11-dimethyl-aminodecylmethacrylate/laurylmethacrylate copolymer, wherein said semi-permeable shell has a high permeability to sodium in the duodenum where the shell is in a hydrated state at neutral pH and has a reduced permeability to sodium in the cecum and colon where it is in a collapsed-impermeable state when the pH is 5 or 6, whereby as the core-shell composition passes from the duodenum to the cecum and colon its permeability to sodium decreases.

2. The method of claim 1 wherein said animal subject is suffering from hypertension, chronic heart failure, end stage renal disease, liver cirrhosis, chronic renal insufficiency, fluid overload, or sodium overload.

3. The method of claim 1 wherein extra cellular water is removed from said animal subject.

4. The method of claim 1 wherein a beneficial effect is observed on fluid management, blood pressure control, and/or interdialytic weight gain.

5. The method of claim 1 wherein said animal subject is suffering from a disease characterized by a presence of abnormal quantities of sodium and/or water in the body of said animal subject.

6. The method of claim 1 wherein said animal subject is resistant to diuretic treatment and is suffering from hypertension, chronic heart failure, end stage renal disease, liver cirrhosis, chronic renal insufficiency, fluid overload, or a combination thereof.

7. The method of claim 1 wherein treatment of said animal subject reduces formation of edema after a cardiac event.

8. The method of claim 1 wherein said animal subject is suffering from volume/salt sensitive diastolic heart failure.

9. The method of claim 1 wherein said composition is co-administered with a diuretic, an angiotensin converting enzyme (ACE) inhibitor, an α-blocker, a β-blocker, an angiotensin II receptor blocker, or a combination thereof.

10. The method of claim 1 wherein said composition is co-administered with a laxative.

11. The method of claim 1 , said cation exchange core being capable of binding sodium in an upper gastro-intestinal tract and the semi-permeable shell being characterized by decreased permeability to the bound sodium in a lower gastro-intestinal tract relative to the permeability exhibited by the core-shell composition to said bound sodium in the upper gastrointestinal tract.

12. The method of claim 11 wherein said composition is co-administered with a diuretic, an angiotensin converting enzyme (ACE) inhibitor, an α-blocker, a β-blocker, an angiotensin II receptor blocker, or a combination thereof.

13. The method of claim 1 wherein said cation exchange core comprises a structural unit selected from the group consisting of

14. The method of claim 13 , said cation exchange core being capable of binding sodium in an upper gastro-intestinal tract and the semi-permeable shell being characterized by decreased permeability to the bound sodium in a lower gastro-intestinal tract relative to the permeability exhibited to said bound sodium in the upper gastrointestinal tract.

15. The method of claim 1 wherein the semi-permeable shell comprises the poly-11 trimethylammonioundecylmethacrylate polymer.

16. The method of claim 1 wherein the semi-permeable shell comprises the 11-dimethyl-aminodecylmethacrylate/laurylmethacrylate copolymer.