A composition comprising as the active ingredient one or more of a tiacumicin compound, a stereo-isomer thereof, a polymorph thereof or a solvate thereof, in combination with an excipient, selected from the group consisting of a xanthan gum, carrageenan, sodium alginate, guar gum, water dispersible cellulose (microcrystalline cellulose and sodium carboxymethylcellulose) and mixtures thereof is provided. Further, use of an excipient, selected from the group consisting of a xanthan gum, carrageenan, sodium alginate, guar gum, water dispersible cellulose (microcrystalline cellulose and sodium carboxymethylcellulose) and mixtures thereof as an anti-foaming agent in a composition comprising as the active ingredient one or more of a tiacumicin compound, a stereo-isomer thereof, a polymorph thereof or a solvate thereof is provided.