Rasashastra deals with the Rasa Aushadhis, the drugs of metallic and mineral origin. Mercury is used
in most of the Rasaaushadhis. The toxicity of Mineral and metallic preparations are reduced to such an
extent by various procedures of Shodhana, Marana etc. that Mercury converts its inherent property of
toxicity into medicinal property. Rasa Aushadhis works quickly on the body because due to their small
particle size, their absorption starts from the oral mucosa itself. The action of drugs depends largely
upon the Anupana i.e. the vehicle for the drug. Rasacharayas have mentioned various Rasa
preparations like Bhasmas, Parpati, Pottali, Manduras, Karpooras etc. along with their doses, dose
schedule and Anupana / Sahapana etc. The principles of Rasaaushadhis when correlated in modern
era are found to be scientifically accurate. We may say that Rasacharyas had already mastered the
science of nanotechnology, purification, action of metabolic catalysts, biotransformation and
preservation of medicines. The Ayurvedic drugs can be harmful for our body when not administered in
proper dosage as per mentioned in classic literatures.
The influence of Einstein's effective viscosity on sedimentation at very small particle volume fraction
