Hospitalized patients receiving β lactam antibiotics develop diarrhea and higher rates reported in those receiving clindamycin. Clostridiumdifficile is recognized as a cause of antibiotic associated diarrhea, colitis and pseudomembranous colitis. Contributory factors include: advance age, severity of underlying illness.C.difficile has the ability to temporarily colonize newborn humans and calves, suggests that the gastrointestinal tracts of young animals may be a major reservoir.C.difficile is recognized enteric pathogen in animals including companion animals and food animals. Clinical features include: asymptomatic carriage in neonates to a fulminant, relapsing, and occasionally fatal colitis. Initial therapy for pseudomembranous colitis includes discontinuation of offending antibiotic regimen, fluid replacement and electrolyte losses. Mild to moderate infection with metronidazole,severe to recurrent cases with vancomycinTherapy with probiotic such as Sacchromyces boularadii is beneficial. Antibiotic misuse in humans and production animals must be addressed.