Changes

The first tetrad is also known as ''Bheshaja'' or the ''Aushadha''(medicine) ''Chatushka''. This tetrad deals with various medicines to be used in various forms either externally or internally.  

The first tetrad is also known as ''Bheshaja'' or the ''Aushadha''(medicine) ''Chatushka''. This tetrad deals with various medicines to be used in various forms either externally or internally.  

* The first chapter [[Deerghanjiviteeya Adhyaya]], explains important concepts such as [[Deerghanjiviteeya Adhyaya#Three Sharira Dosha and two Manas Dosha|''Tridosha'' (''Vata, Pitta and Kapha'')]], [[Deerghanjiviteeya Adhyaya#Rasa (taste sensations)|''Rasa''(taste)]], [[Deerghanjiviteeya Adhyaya#Six Basic Principles for direct knowledge|''Shat siddhanta'' (six basic principles)]], etc. which are integral to Ayurveda and used extensively throughout [[Charak Samhita]]. Besides these technical terms, the first chapter describes various medicines, like ''Phalini Dravya'' (therapeutically useful fruits as drugs), ''Moolini Dravya''(therapeutically useful roots as drugs), ''Mahasneha'' (four kinds of fats), ''Lavana''(salts), various types of ''mutra''(urine) and ''ksheera''(milk). The chapter emphasizes on the rational use of medications, since indiscriminate use of even good medicines can cause more harm than good. The chapter then goes on to explain the important concept of ''Trisutra'' (three principles of Ayurveda) i.e. ''hetu'' (causes), ''linga''(signs and symptoms) and ''aushadha'' (medicine).  

* The first chapter [[Deerghanjiviteeya Adhyaya]], explains important concepts such as [[Deerghanjiviteeya Adhyaya#Three Sharira Dosha and two Manas Dosha|''Tridosha'' (''Vata, Pitta and Kapha'')]], [[Deerghanjiviteeya Adhyaya#Rasa (taste sensations)|''Rasa''(taste)]], [[Deerghanjiviteeya Adhyaya#Six Basic Principles for direct knowledge|''Shat siddhanta'' (six basic principles)]], etc. which are integral to Ayurveda and used extensively throughout [[Charak Samhita]]. Besides these technical terms, the first chapter describes various medicines, like ''Phalini Dravya'' (therapeutically useful fruits as drugs), ''Moolini Dravya''(therapeutically useful roots as drugs), ''Mahasneha'' (four kinds of fats), ''Lavana''(salts), various types of ''mutra''(urine) and ''ksheera''(milk). The chapter emphasizes on the rational use of medications, since indiscriminate use of even good medicines can cause more harm than good. The chapter then goes on to explain the important concept of ''Trisutra'' (three principles of Ayurveda) i.e. ''hetu'' (causes), ''linga''(signs and symptoms) and ''aushadha'' (medicine).  

* The second chapter ([[Apamarga Tanduliya Adhyaya]]) deals specifically with herbs and medicines to be used during and after Panchakarma (five methods of bio-purification). Thus, the first two chapters of this tetrad describe various medicines to be used internally.  

* The second chapter ([[Apamarga Tanduliya Adhyaya]]) deals specifically with herbs and medicines to be used during and after [[Panchakarma]] (five methods of bio-purification). Thus, the first two chapters of this tetrad describe various medicines to be used internally.  

* The third chapter ([[Aragvadhiya Adhyaya]]) advocates the use of topical medications, or medicines to be applied externally, i.e.,''lepa'' etc.  

* The third chapter ([[Aragvadhiya Adhyaya]]) advocates the use of topical medications, or medicines to be applied externally, i.e.,''lepa'' etc.  

* The fourth chapter ([[Shadvirechanashatashritiya Adhyaya]]) provides details of fifty ''Mahakashaya''(or five classes of groups of ten medicines, and six hundred evacuatives) to be used in various diseases. Overall, this ''Chatushka'' provides a list of drugs to be used in various forms in a variety of diseases.

* The fourth chapter ([[Shadvirechanashatashritiya Adhyaya]]) provides details of fifty ''Mahakashaya''(or five classes of groups of ten medicines, and six hundred evacuatives) to be used in various diseases. Overall, this ''Chatushka'' provides a list of drugs to be used in various forms in a variety of diseases.