Medicinal plants used by rural communities in the arid zone of Viesca and Parras Coahuila in northeast Mexico.

This study is the first record of medicinal plants in the southwest of the Coahuila state, an arid zone where extreme dry conditions prevail. One hundred twenty-two residents (in sixteen communities) were interviewed. The residents were questioned with a questionnaire-guided ethnomedical survey protocol about the various plants used.