Methods of treating travelers diarrhea and hepatic encephalopathy

1. A method of treating a subject having Travelers' Diarrhea (TD) comprising:

identifying a subject having TD that also has hepatic insufficiency;

determining if the subject's Child-Pugh score is Child-Pugh Class C or if the subject's model end stage liver disease (MELD) score is 25 or greater;

administering rifaximin cautiously to the subject if his or her Child-Pugh score is Child-Pugh Class C or if his or her MELD score is 25 or greater.

2. The method of claim 1 , wherein the hepatic insufficiency is hepatic encephalopathy.

3. The method of claim 1 , wherein the subject is treated for 12 to 72 hours.

4. The method of claim 1 , wherein the rifaximin is administered at 200 mg TID.

5. The method of claim 1 , further comprising testing the subject for hepatic insufficiency.

6. The method of claim 1 , wherein the TD is caused by bacterial, virus, or protozoan infection.

7. The method of claim 1 , wherein the TD is caused by E. coli.

8. The method of claim 7 , wherein the E. coli is enterotoxigenic E. coli.

9. The method of claim 1 , wherein the subject is a human.

10. The method of claim 1 , wherein the rifaximin comprises tablets for oral administration comprising one or more of colloidal silicon dioxide, disodium edetate, glycerol palmitostearate, hypromellose, microcrystalline cellulose, propylene glycol, red iron oxide, sodium starch glycolate, talc, or titanium dioxide.

11. The method of claim 1 , wherein the duration of diarrhea was significantly shorter in a subject treated with rifaximin compared to an untreated subject.

12. The method of claim 1 , wherein the clearance rate of rifaximin is decreased in a population of subjects with hepatic insufficiency as compared to a population of subjects without hepatic insufficiency.

13. The method of claim 1 , wherein the elimination rate of rifaximin is decreased in subjects with hepatic insufficiency as compared to subjects without hepatic insufficiency.

14. The method of claim 1 , wherein the systemic exposure to rifaximin is increased in a population of subjects with hepatic insufficiency as compared to a population of subjects without hepatic insufficiency.

15. The method of claim 1 , wherein the serum level of rifaximin is increased in a population of subjects with hepatic insufficiency as compared to a population of subjects without hepatic insufficiency.