Abstract Context: This study evaluated the in vitro and in vivo antidiarrheal activity, oral acute toxicological profile, and developed a chemical fingerprint of Berberis aristata Linn. (Berberidaceae).Materials and methods: The ethanol (by maceration) and aqueous (by Soxhlet) extracts of Berberis aristata bark were used for the study. The study involved the antimicrobial (minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) by micro dilution) and antidiarrheal (castor oil induced diarrhea, charcoal motility)tests. The active principle, berberine was characterized by different spectroscopic and chromatographic techniques.