1. A pharmaceutical composition for topical rectal administration in the form of a foam, wherein the composition comprises rifaximin in the form of nanoparticles. The composition of claim 1, further comprising an aqueous or non-aqueous vehicle. The composition of claim 2, wherein the non-aqueous carrier is one or more pharmaceutically acceptable alkanols； one or more pharmaceutically acceptable vegetable oils； or one or more pharmaceutically acceptable organic esters. 4. The composition of claim 3, wherein the water soluble alkanol is ethanol； propylene glycol； glycerol； polyethylene glycol； polypropylene glycol； propylene glycol； glyceryl ester or mixtures thereof. 5. The composition according to claim 2, where the carrier includes a water-soluble alkanol and water, and where wt./mass. the ratio of water soluble alkanol to water is from 0.05: 10 to 10: 0.05. The composition of claim 2, wherein the carrier is from 10% w / w. up to 90% wt./mass. of the total weight of the composition. 7. The composition of claim 2, wherein the carrier comprises water in an amount of from 20% w / w. up to 90% wt./mass. from the total weight of the composition, and water-soluble alkanol in an amount of from 0% wt./mass. up to 50% wt./mass. from the total weight of the composition. 8. The composition of claim 2, further comprising at least one surfactant. The composition of claim 8, where the surfactant is present in an amount of from 0.1 to 1.0 wt./mass. of the total weight of the composition. 10. The composition of claim 1, further comprising at least one propellant. The composition of claim 10, where the propellant is present in an amount of from 2 to 20% wt./mass. of the total weight of the composition. 12. The composition of claim 1, further comprising at least one salt�1. Фармацевтическая композиция для местного ректального введения в виде пены, где композиция включает рифаксимин в форме наночастиц.2. Композиция по п.1, дополнительно включающая водный или неводный носитель.3. Комп
