Pharmaceutical compositions comprising rifaximin

A pharmaceutical composition comprising a therapeutically effective amount of at least one rifaximin;

• a therapeutically effective amount of at least one alkaloid or derivative thereof;
• and one or more pharmaceutically acceptable excipients comprising carriers, diluents, fillers, binders, lubricants, glidants, disintegrants, bulking agents, flavorants or any combination thereof.

A method of treating systemic infections as well as colonic diseases in a patient in need of such treatment, the method comprising:

• administering a pharmaceutical composition comprising (i) a therapeutically effective amount of rifaximin;
• (ii) a therapeutically effective amount of at least one alkaloid or derivative thereof;
• and (iii) one or more pharmaceutically acceptable excipients comprising carriers, diluents, fillers, binders, lubricants, glidants, disintegrants, bulking agents, flavorants or any combination thereof.

A method of making a pharmaceutical composition that enhances the bioavailability of rifaximin, the method comprising:

• mixing a therapeutically effective amount of rifaximin and a therapeutically effective amount of at least one alkaloid or derivative thereof with one or more pharmaceutically acceptable excipients to make the pharmaceutical composition.

The method according to claim 11, wherein the at least one alkaloid comprises piperine, tetrahydropiperine, cis-piperine, trans-piperine, cis-trans piperine, trans,cis-piperine, cis,cis-piperine, trans,trans-piperine or a combination thereof.

A kit for treating disease caused by caused by Clostridium difficile infection and infections caused by Gram-positive and Gram-negative bacteria, the kit comprising a therapeutically effective amount of rifaximin and a therapeutically effective amount of at least one alkaloid or derivative thereof, wherein the rifaximin is in a separate composition from the at least one alkaloid or derivative thereof.

A method of enhancing the bioavailability of rifaximin, the method comprising:

• providing a therapeutically effective amount of rifaximin and providing a therapeutically effective amount of at least one alkaloid or derivative thereof.