Pharmacological Review on Purification of Visha Dravyas (Poisonous Plants) According to Ayurveda

Visha possess properties of Vyavayi(Pervading or diffusing action), Vikasi(Dispersed through out the body causes destruction of Ojas and Dhatu Kshaya or depletion of the body tissues, Ushna(Heat), Teekshna(Penetrating), Ruksha(Dry), Sukshma(Minuteness), Ashukar(Quick or immediate action), Vishada(Clearness), Laghu(Light), Avyakta Ras(Taste sometimes palatable and sometimes not palatable or the taste is hidden) and Apaki(Not digestible). It distributes in the whole body immediately first and later undergoes digestion. Hence causes the vitiation of Dosha(Vata–Pitta–Kapha) and Dhatu(Rasa–Rakta–Mamsa–Meda–Asthi–Majja–Shukra) and produces the poisonous effects. The drugs which act against and subside poisonous effects on the vitiated Dosha(Vata–Pitta–Kapha) and Dhatus viz; Rasa(Plasma), Rakta(Blood), Mamsa(Muscle tissue), Meda(Fat), Asthi(Bones), Majja(Bone marrow), Shukra(Semen) are called as Vishaghna Dravyas. Visha has been defined as a substance which is destructive or life threatening and causes Shoka(Sadness). There are many poisonous drugs described in Ayurvedic classics along with their antidotes and their pharmacological actions after purification. Poisonous plants may be categorized under the chemical structure of the toxic constituents, their phylogenetic relationship viz; plants that are poisonous to eat, plants that are poisonous upon contact, plants that produce photo sensitization, and plants that produce airborne allergies conditions in the body. The phytotoxins, comprise a vast range of biologically active chemical substances, such as alkaloids, polypeptides, amines, glycosides, oxalates, resins, toxalbumins. The present review describes the different process of detoxification or purification methods (Sodhana) in Ayurvedic system of medicines. So here an attempt is made to screen the Visha Dravyas(Poisonous plants) and their purification methods in various media along with their Rasa, Guna, Veerya and Vipaka, Prabhava from the various Ayurvedic classical texts along with their pharmacological actions.