Clostridium Difficile Agar is a solid medium employed for the isolation of Clostridiumdifficile. In this medium, the selective agents D-Cycloserine and Cefoxitin inhibit the growth of most Enterobacteriaceae, Streptococcusfaecalis, Staphylococci, Gram-negative non-sporing anaerobic bacilli, and Clostridiumspp. other than Clostridiumdifficile, which may be found in large numbers in faecal samples. The growth of this species acidifies the medium and causes the Phenol Red indicator to shift to yellow. Egg Yolk Suspension reduces the toxic effect of the organic peroxides that might accumulate in the medium and allows for the detection of lecithinase and lipase activity. Proteose Peptone supplies amino acids and other nitrogenous compounds. Fructose is the fermentable carbohydrate. Sodium Chloride maintains the osmotic balance and the Potassium Phosphates serve as pH buffers. Agar is the gelifying agent.