The traditional knowledge of tribals was scientifically validated where investigation was undertaken to evaluate in vivo anthelmintic efficacy of Nigella sativa (Kaloji), Swertia chirata (Chirayata)and Piper longum (Pippali) on gastrointestinal nematodes in naturally infected goats. Besides the anthelminitc efficacy of the aforesaid indigenous plants, the haematological and clinical observations were made to find out their safety levels in goats. The extractability and phytochemical composition of N. sativa, S. chirata and P. longum were also determined to find out the presence of bioactive principles in the indigenous plants.