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\def\RunningAuthor{Renu Rathi et al.}
\firstPage{938}
\articleType{Review Article}
\receivedDate{02 Jun 2020}
\acceptedDate{14 Jul 2020}
\revisedDate{19 Jun 2020}
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\title{Concept of \textit{Rasayana}: Unique Ayurvedic Approach in Preventing Infectious Diseases with Special Emphasis on COVID-19}
\author{Amit~S.~Deshmukh\textsuperscript{1},  
            Renu~Rathi\textsuperscript{*}\textsuperscript{1}, 
            Bharat~Rathi\textsuperscript{2}~\\[5pt]{\textsuperscript{1}Department of Kaumarbhritya, Mahatma Gandhi Ayurveda College,  Hospital \& Research Centre, Salod (H), Wardha, Maharashtra, India}~\\{\textsuperscript{2}Department of Rasa Shastra, Mahatma Gandhi Ayurveda College,  Hospital \& Research Centre, Salod (H), Wardha, Maharashtra, India}}

\begin{abstract}
Rasayana is one of the unique branches of Ayurveda \& it is suggested to increase \textit{ojas}. Modern scientific observation's on \textit{Rasayana} shows that rejuvenating drugs can protect the body against detrimental effects of the atmosphere in which we survive, by augmenting the individual's capability to fight against disease-carrying organism through stimulating the immune system. The \textit{Rasayana} therapy improves the merits of rasa, build up to it with nutrients so one can attain prolonged existence, memories, intellect, freedom from diseases, quality in lustre, complexion and voice, optimal improvement of physique and all sense organs. Rasayana is very useful to increase the immunity of the person to keep him away from disease. \textit{Rasayana} herbs have antioxidant properties which prevent the damage caused by free radicals. According to Ayurveda, Rasayana brings about proper nourishment, growth \& enhanced function of all sevens \textit{dhatus} (tissues). Rejuvenation therapy affects body \& mind at the same time it checks the effect of early ageing on both, and enhance the body's resistance to disease. Considering the grave situation of COVID -19 where effective medicine is yet to be invented, one should develop a healthy immune system for survival. Rasayana drugs provide nutritional supplementation along with enhancing immunity to fight against viral infections such as COVID -19.
\end{abstract}\def\keywordstitle{Keywords}

\begin{keywords}Rasayana,\newline Antioxidants,\newline COVID -19,\newline Viral Infections
\end{keywords}
\twocolumn[ \maketitle {\printKwdAbsBox}]
\makeatletter{\raggedright\textsuperscript{*}Corresponding Author\par Name:\ Renu~Rathi~\\ Phone:\  9011058302~\\  Email:\ renu.22@gmail.com
        \par}\vspace*{-11pt}\hrulefill\par{\fontsize{12}{14}\selectfont ISSN: 0975-7538}\par% 
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\section{ Introduction}
Rasayana means to increase the essence of each \textit{dhatu}, which starts from Rasa \textit{dhatu}. The immunity of a person is increased and keeps him away from diseases due to regular use of Rasayana. The person becomes healthy and strong. Thus \textit{Rasayana} helps in obtaining the optimum nourishment to the \textit{dhatus}. With the help of \textit{Rasayana}, one can attain longevity, returns to youthfulness, strength, \& gets sharp memory, mental power \& freedom from disease. According to Ayurveda\textit{, Rasayana} therapy affects the body \& mind and brings balance between the physical \& psychic wellbeing. \textit{Rasayana} averts the effect of early ageing, develops intelligence \& boosts the body resistance against the diseases\unskip~\citep{878308:20262959}. 

Rasayana is a select branch of management controlling the primary aspect of the body viz. \textit{dhatus}, \textit{agni} and \textit{srotas}. \textit{Rasayana} therapy boosts the immune system. The adjective \textit{Ojaswi} is used to portray those people who maintain their immunity and keep themselves healthy in every season and all phases of life. \textit{Rasayan} imparts a bright look, sharp memory, high performance\unskip~\citep{878308:20262948}. Hence in this paper author has attempted to highlight the concept of \textit{Rasayana} described in Ayurveda and understand its importance in preventing the infectious diseases and ageing process \& improving the immunity. In the present era, there is a gradual decrease in immunity in most human beings. Many new diseases are spreading worldwide nowadays. It is necessary to prevent such diseases with the help of Rasayana therapy. 
    
\section{Materials and Methods}
 The available literature is reviewed through various medical research databases like PubMed, Google Scholar, Scopus online, other National and International research databases from the year 2000 to 2020. The terms entered for search are ``Ra\textit{sayana,} Rasayana drugs, Immunity, ``Covid-19''.
    
\section{Results and Discussion}
\textbf{Definition of Rasayana}

Rasayana is defined as the way of achieving brilliant rasadi seven \textit{dhatus}. \textit{Ahara}, \textit{vihara} \& \textit{aushadhi} dravyas which promotes \textit{rasadi} seven \textit{dhatus}\unskip~\citep{878308:20262947}. 

\textbf{Classification of Rasayana}

\textit{Rasayana} is classified into two types based on needs,


  
  \begin{enumerate}
  \item \relax \textit{Kamya} \textit{Rasayana}- which promotes natural health. It increases the energy level, immunity \& general health.
  \end{enumerate}
  \textit{Pranakamya}, \textit{medhakamya} and \textit{srikamya} are examples of \textit{kamya Rasayana}, which are promoters of vitality and longevity, intelligence and complexion.

2. \textit{Naimittika Rasayana}- which helps to fight against a specific disease.

On the basis of place of therapy, \textit{Rasayana} is again divided into \textit{Kutipraveshika Rasayana} \& \textit{Vatatipik Rasayana}.

\textbf{Mechanism of action of Rasayana}

Rasayana promotes nutrition through enhancement of the nutritional quality of \textit{rasa}, means nutritional enhancement (quality of \textit{rasa} \textit{dhatu}) by subsequent nourishment of succeeding dhatus, also improving \textit{Agni} (\textit{dhatwagni} means on enzyme level) promoting improve metabolism \& increasing microcirculation through channels (\textit{srotas}) in the body as shown in Figure~\ref{f-2b3dce37db5e}. Various researches suggest that the Rasayana drugs are strong rejuvenators, provide additional nutritional supplements \& possess high antioxidant activity. They also show antagonistic actions on the oxidative stressors, which used mainly in ageing and other chronic disorders\unskip~\citep{878308:20262949}.The ojas plays a significant role in maintaining good health \& vitality. It is the ultimate product of digestion \& nutrition of all seven \textit{dhatus} (tissues), as well as it is prime energy reserve of the entire body. \textit{Ojas} shows the overall condition or state of the body as a whole. Immunity, longevity, strength and resistance depend on the quality \& quantity of ojas. Diseases \& loss of immunity arises from depletion \textit{ojas}. All rejuvenation therapy is targeted at improving the \textit{ojas} of the body\unskip~\citep{878308:20262953}. 


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\caption{\boldmath {Mode of action of Rasayana}}
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\egroup
\textit{Rasayana} not only rejuvenates the body \& mind, but it also prevents the diseases. There are various drugs explained which are having qualities of maintaining health, preventing diseases \& increasing the life span of individuals. They all are group as \textit{Rasayana}.\textit{Rasayana} drugs affecting \textit{ojas}, improving immunity \& resistance to the diseases. In Ayurveda, ojas has been explained as an essence of all \textit{dhatus} \& considered to be an excellent body element. Therefore, the excellence of body \& mind depends upon the quality of \textit{ojas}. Therefore, resistance to the disease of the body depends on the quality \& quantity of \textit{ojas}\unskip~\citep{878308:20262951}.

\textit{\textbf{Rasayana}} \textbf{ Drugs for Specific System}

Respiratory system- \textit{Chayavanprash, Vardhaman Pippli Rasayana}.\textbf{\space }

Digestive system - \textit{Pippali, Bhallataka, Haritaki}.

Circulatory system - \textit{Amalaki, Bhringaraj}. 

Muscular system - \textit{Ashwagandha, Bala}.

Nervous system - \textit{Ashwagandha, Shankhpushpi, Brahmi, Vacha}.

Reproductive system - \textit{Ashwagandha, Kapikacchu, Satavari, Vidarikanda}.

Urinary system- \textit{Punarnava, Shwadransta}.

Excretory system - \textit{Krimighna, Kutaja, Vara}.

\textit{\textbf{Rasayana}} \textbf{ suggested for different age groups}

One to ten years ----\textit{Balya} (Childhood) -----\textit{Vacha, Suvarna Bhasma}.

Eleven to twenty years ----\textit{Vriddhi} (Growth) -----\textit{Ashwagandha, Bala.}

Twenty-one to thirty years ----- \textit{Chhavi} (Beauty) -----\textit{Amalaki, Loha Bhasma}.

Thirty-one to Forty years----\textit{Medha} (Intellect) ------ \textit{Shankhapushpi, Brahmi}.

Forty-one to Fifty --- 50 years ---- \textit{Tvak} (nourishment of Skin) -- \textit{Maka, Priyal}

Fifty-one to Sixty years ----- \textit{Drishti} (Vision) ----- \textit{Triphala, Shatavari},

Sixty-one to Seventy years ---- \textit{Shukra} (Semen) ----- \textit{Ashvagandha, Kappikacchu}.

Seventy-one to Eighty years ----\textit{Vikrama} (Physical) ---- \textit{Bala, Amalaki}.

Eighty-one to ninety years-----\textit{Buddhi} (Wisdom) ----\textit{Brahmi, Shankhapuspi}.

Ninety-one to Hundred years----\textit{Karmendriya} ----- \textit{Ashwagandha, Bala}. Single \textit{Rasayana} Drugs

1. \textit{Amalaki}.

 2. \textit{Guduchi}.

 3. \textit{Ashwagandha}.

 4. \textit{Brahmi}.

\textbf{Compound Formulations }

 1. \textit{Brahmi Rasayan}.

 2. \textit{Amalaka Rasayan}.\textbf{\space }

\textbf{\space }3. \textit{Triphala Rasayan}.

 4. \textit{Chavyanprash}.

 5. \textit{Brahma Rasayan}.

In vivo study on Tinospora, cordfolia suggests that the \textit{Rasayana} (particular \textit{Madhur}\textit{vipaki}) primarily activate immune cells, leading to secretion of cytokines, which in turn act on multiple target organs to produce the numerous effect attributed to these treatments \unskip~\citep{878308:20262954}.  \textit{Rasayana} is enhancing the natural killer cell activity in the normal cell as well as tumour-bearing animals. \textit{Ashwagandha}\textit{Rasayana} \& \textit{Brahma Rasayana} found to activate antibody-dependent cytotoxicity \& activates macrophages. The \textit{Rasayana} herbs seem to exert their effect through immunosuppressant, immunostimulant \& immunoadjuvant activities or by affecting the effector arm of the immune response. \textit{Rasayana} drugs act as potent antioxidants \& neuroendocrine immunomodulators considering the grave situation of COVID -19 where effective medicine is yet to be invented. One should develop a healthy immune system for survival in such conditions. There are some vitamins \& trace elements which are vital for the regular functioning of the immune system. Besides, supplementation of these has shown encouraging impact in enhancing immunity in viral infections. Balanced nutrition which can help in maintaining immunity is essential for the prevention \& management of viral infections\unskip~\citep{878308:20262946}. The disease preventive \& health promotive approach of Ayurveda, which takes into consideration the whole body, mind \& spirit while dealing with the maintenance of health, promotion of health \& treating ailments in a holistic way \& increasing acceptability in the world\unskip~\citep{878308:20262952}. COVID-19 like infections are an example of Prakriti-prakopa by man and lessons should be learnt to avoid the same in future by adopting these Ayurveda preventive measures such as \textit{Ritucharya} \textit{Dincharya}, \textit{Rasayana} therapy and safe lifestyle \unskip~\citep{878308:20262950}.
    
\section{Conclusion}
 Rasayana does nourishment of all \textit{dhatus} (tissues \& cells), thus improving resistance against the infectious disease by strengthening immunity. \textit{Rasayana}, through its effect, causes effective elimination of \textit{malas} (waste products) from the body thus causes the balance between the metabolism \& excretion. It prevents muscles \& tissue damage, thus delays the ageing process. Thus, \textit{Rasayana} not only rejuvenates the body \& mind, but it also prevents infections (Viral infections such as COVID -19) \& diseases.
\section*{Acknowledgement}Author would like to thanks DMIMSU for motivation \& all necessary help for writing this article.

\textbf{Funding Support}

The authors declare that they have no funding support for this study.

\textbf{Conflict of Interest}

The authors declare that they have no conflict of interest for this study.
    

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