STUDY OF ACUTE TOXICITY AND ANTI INFLAMMATORY ACTIVITY OF Andrographis paniculata Nees (ACANTHACEAE) Pubali Borgohain 1 and B.B. Kakoti 2 1 Centre for Biotechnology and Bioinformatics, Dibrugarh University, Assam (Presently, Aryabhatta Academy, Sivasagar, Assam) 2 Department of Pharmaceutical Sciences, Dibrugarh University, Assam E-mail: pubaliborgohain07@gmail.com Abstract- The aim of the experiment was to study the anti-inflammatory activity of methanolic extract of Andrographis paniculata Nees on a suitable animal experimental model. This plant has been traditionally used for treatment of respiratory diseases, high blood pressure, skin diseases etc. Anti inflammatory activity of the aqueous extract of the plant was observed using carrageenan induced rat paw oedema. The test extract at dose 200 mg/kg of rat body weight exhibited 55.10 % inhibition of rat paw oedemas. The methanolic root extract displayed a significant anti inflammatory activity. Keywords: Carrageenan, inflammation, methanolic extract, rat paw oedema, Introduction Inflammation is the defense mechanism adopted by the body against free radicals, accompanied with symptoms of pain, heat, redness, swelling as well as loss of function at the site of inflammation (Moldoveanu et al., 2009). Nitric oxide synthases (NOSs) are a family of enzymes that are responsible for the synthesis of nitric oxide (NO) from the amino acid L- arginine in the body. The expression of inducible NOS (iNOS) can only be induced by inflammatory stimuli and contribute to the large amount of NO production (Yu et al., 2018). Nitric oxide (NO) is recognized as an important intracellular and intercellular biological active molecule that acts diverse physiological and patho-physiological functions in the body, including cardiac contractility and regulation of vasodilation (Vanhoutte, 2018). Andrographis paniculata Nees (Acanthaceae), occurring in South India and South East Asia (called as kalmegh and chuanxinlian, respectively), is an important ingredient used in herbal medicinal preparations (including, anti-inflammatory) in both traditional Indian and Chinese medicine (Chao and Lin, 2010; Akbar, 2011). The present study aims at evaluating the anti- inflammatory activity of A. paniculata extract, thereby attempting to verify the textual and orally transmitted claims. International Journal of Science, Environment ISSN 2278-3687 (O) and Technology, Vol. 8, No 3, 2019, 580 – 584 2277-663X (P) Received May 9, 2019 * Published June 2, 2019 * www.ijset.net