A probiotic composition comprising at least one viable probiotic microorganism having a biological or therapeutic activity in the gastrointestinal tract and a carrier suitable for human consumption is disclosed. The probiotic composition may contain drinking water and electrolytes and the probiotic microorganism may be spores of a probiotic microorganism. Also provided are methods of treating acute or chronic diarrhea and of improving immune function, digestive health, and/or intestinal flora by administering the probiotic composition. In addition, a food additive comprising at least one viable probiotic microorganism having a biological or therapeutic activity in the gastrointestinal tract and a carrier suitable for human consumption is provided.
