The meaning of chikitsa is rejuvenating therapy. It means getting better from a sickness and going back to your old or usual condition. In addition to treating illness in the sick, rejuvenation therapy helps to maintain and promote health. Rasa is similar to what modern physiology refers to as lymph and plasma. Rasayana, or rejuvenation, is the process of preserving and replenishing the fluids and “juiciness” in our bodies. It also enhances the mental and physical capacities of a healthy individual. It is widely known to improve skin tone and texture, modulate voice, and increase the sensitivity of sense organs. By restoring the vital fluids in our bodies, it helps us avoid sickness. There are several means by which Rasayana can be connected to the current condition: (1) Antioxidants' action, (2) How immunomodulation works, (3) The hemopoietic impact, (4) Adaptogenic action, (5) The anti-aging impact, (6) The anabolic effect, (7) The role of nutrients, (8) Neuron-protective action.

There are different types of Rasayana for Different Illnesses:

This article is a narrative review aimed at summarizing and critically analyzing the pharmacological basis and therapeutic applications of Rasayana herbs in Ayurveda. The review synthesizes classical Ayurvedic literature along with contemporary scientific evidence from preclinical and clinical studies.⁸

A comprehensive literature search was conducted using PubMed, Scopus, Web of Science, ScienceDirect, and Google Scholar. The search covered publications from January 1956 to December 2025. The final updated search was performed in April 2026.

The following finalized search strategies were used:

PubMed:

(“Rasayana” OR “Ayurveda Rasayana”) AND (“Withania somnifera” OR “Bacopa monnieri” OR “Tinospora cordifolia”)

Scopus:

TITLE-ABS-KEY (“Rasayana” AND Ayurveda)

Web of Science:

TS = (“Rasayana” AND Ayurveda)

ScienceDirect:

“Rasayana therapy” AND Ayurveda

Google Scholar:

“Rasayana herbs” AND pharmacology AND Ayurveda

Reference lists of eligible studies were also manually screened to identify additional relevant records.

Studies were included if they

Studies were excluded if they

Relevant studies were screened based on title and abstract. Full-text articles were reviewed for relevance to Rasayana pharmacology, mechanisms of action, therapeutic applications, safety, and translational limitations.

Key information extracted included

The screening process was conducted in two stages. First, titles and abstracts were evaluated to remove irrelevant publications. Subsequently, full-text articles were assessed for eligibility based on predefined inclusion and exclusion criteria. Studies that fulfilled the criteria were included for qualitative synthesis. Data extraction was performed manually from the selected studies. Extracted variables included the botanical name of the herb, major phytoconstituents, pharmacological mechanisms, type of study (in vitro, animal, or clinical), therapeutic outcomes, and safety considerations. The process of literature identification, screening, eligibility assessment, and the final inclusion of studies is illustrated in Figure 1. In addition, the available evidence was categorized according to study type, including in vitro experiments, animal studies, and human clinical trials. This approach helped differentiate the strength of available scientific evidence and ensured a balanced interpretation of pharmacological findings. The study selection process followed PRISMA-style guidance. Titles and abstracts were independently screened by two reviewers, followed by full-text assessment for eligibility. Any disagreements were resolved through discussion and consensus. The final set of studies was included for qualitative synthesis.

A detailed supplementary table listing the clinical studies included for each herb, including citation, study design, sample size, population, dose, formulation, duration, endpoints, and key findings, has been provided to enhance transparency. The PRISMA flow diagram was updated to ensure consistency between the figure and text. Reasons for exclusion at the full-text stage included duplicate records, non-English publications, absence of primary pharmacological or clinical data, irrelevant topic scope, and insufficient methodological details.

As a narrative review, this study does not involve quantitative meta-analysis or formal risk-of-bias scoring. The findings are dependent on the quality and heterogeneity of the included literature.

Although this review is narrative in nature, a basic risk-of-bias assessment was conducted to evaluate the reliability of the included studies. Preclinical studies were assessed based on methodological clarity, experimental design, and reproducibility. Clinical studies were evaluated for sample size, study design (randomized or non-randomized), and outcome reporting. Studies with insufficient methodological transparency were interpreted with caution.

Evidence was categorized according to the level of available scientific support as follows:

Level I – Strong evidence: Randomized-controlled trials and systematic reviews.

Level II – Moderate evidence: Controlled clinical studies and well-designed observational studies.

Level III – Preliminary evidence: Animal studies and mechanistic experimental research.

Level IV – Traditional evidence: Historical Ayurvedic texts and ethnomedical documentation.

From the Sanskrit words “Medhya,” which denotes intelligence or wisdom, and “Rasayana,” which indicates rejuvenation, the title “Medhya Rasayana” is obtained. Nootropics are necessary to improve cognitive abilities in cases of cognitive deficiencies that manifest either alone as developmental defects or in conjunction with other neuropsychiatric diseases. Because medicinal herbs have fewer side effects, there has been a major global effort recently to investigate their potential to improve cognitive function. “Medha” means intelligence or memory. The medhyarasayanas used in Ayurveda help guarantee that the medha functions properly so that one can have a healthy life. It also refers to knowing and reacting well to the things that are already present.

Acharya Charaka has classified four drugs in the category of medhyarasayana, although many Ayurvedic drugs are well known for their effects on the brain. To improve mental capacities, these drugs can be used separately or in combination. Among these drugs are

A list of 10 Drava (ingredients) known as Vayahsthapana Dashakaya can be found in Shad virechana shatashriteeya adhyaya and Charaka Samhita Sutrasthana. The Charaka Samhita, a reliable source on Ayurveda, mentions the Vayahsthapana Dashakaya, a compilation of organic minerals and therapeutic herbs.¹¹ The 10 components of Vayahsthapana Dashakaya are Amruta, Abhaya, Dhatri, Mukta, Shveta, Jivanti, Atirasa, Mandukaparni, Sthira, and Punarnava. The Rasayana activity of most of these medications' aids in anti-aging. The benefits of Rasayana treatment, sometimes referred to as a promotive treatment, include longevity, young appearance, and a glowing complexion. Examination of Vayahsthapana Dashakaya's pharmacodynamic, pharmacokinetic, and pharmacological potential as well as their application in anti-aging treatments was the main goal of this study. The information was gathered from reputable Ayurvedic books, research papers, dictionaries, monographs, and websites. An 80% possibility of Deepana action, 70% possibility of Rasayana action, 50% possibility of Balya action, 50% possibility of Medhya action, 40% possibility of Hridya action, 20% possibility of Vrushya action, and 20% possibility of Brunhana action were determined to be important Vayahsthapana Dashakaya actions that help delay aging and its harmful effects.¹²

Drugs are a major part of Chikitsa chatushpada, which is mentioned in the Charaka Samhita next to the role of the doctor. Doctors must have a solid understanding of the medication, because, without it, patients cannot receive the proper care. “Balaaya Hitam Balyam,” which describes things that are advantageous and have the capacity to raise a person's Bala, is the definition of the action Balya. The notion of Bala has been explained at length by a number of Ayurvedic Acharaya. Based on their pharmacological properties, or Karma, Acharya Charaka categorized the drugs into 50 groups, or Mahakashaya. Every Mahakashaya has 10 drugs with similar properties. One of them, Balya Mahakashaya, is present in 10 different drugs. The Charaka Samhita Sutra, sthana 4/7, lists 50 mahakashaya, including Balya Mahakashaya. This mahakashaya contains 10 key medications, including Aindri, Rishabhi, Atirasa, Rishyaprokta, Payasya, Ashvagandha, Sthira, Rohini, Bala, and Atibala. “Balya” is another name for Dravya, which gives the body more energy or strength. The word “mahakashaya” describes a class of medications with related uses.¹³

Ojas is derived from the Sanskrit word for “vigor” or “energy,” and is considered the essence of all bodily tissues and the final outcome of a well-balanced and nourished system. Its presence is synonymous with health, strength, and immunity, while its depletion is associated with disease, weakness, and vulnerability to illness.

Ojas is described in Ayurvedic literature as a subtle, living force that permeates the entire body.¹⁴ It is the most refined result of digestion and metabolism, and represents the essence of the dhatus (bodily tissues). Instead of referring to a particular physical material, it is an idea that encompasses the overall condition of vitality and well-being. According to traditional Ayurvedic texts such as the Charaka Samhita and the Sushruta Samhita, Ojas is defined by attributes like clarity, brightness, stability, and durability. Ojas is the substance of all bodily tissues (dhatus) and the product of digestion and metabolism, according to Ayurveda. The refined energy results in immunity, vigor, and strength. In addition to being a physical substance, ojas is a subtle power that permeates every area of the body and influences both mental and physical health.

Adaptogen, stress relief, and strength. The recent years have witnessed a sharp rise in reports on the health benefits of winter cherry (Withania somnifera), also known as Ashwagandha. Many aspects of human health are being researched currently, including neuroprotective, sedative, adaptogenic, and sleep-related effects. There have also been reports of anti-inflammatory, antibacterial, cardioprotective, and anti-diabetic properties,¹⁹ in addition to reports of reproductive effects and thyrocidal hormone action. The growing body of research on Ashwagandha indicates that it may be a helpful natural remedy for a number of health problems. This narrative review examines the most recent studies and provides a comprehensive overview of the current understanding of Ashwagandha's potential uses, safety concerns, and contraindications. For ages, traditional medical systems, especially Ayurvedic medicine, have utilized Ashwagandha, a plant substance. Research on Ashwagandha's many impacts has been carried out over the years, and the results have indicated that it has a number of positive effects on many physiological systems. It is crucial to keep in mind that research on Ashwagandha is still in progress; additional studies are required to establish its possible therapeutic applications as well as to identify the best dosages and usage times.²⁰ The safety of Ashwagandha should also be taken into account, especially if it is being used with other drugs or supplements. Thus, further research is required to shed light on the possible advantages and disadvantages of utilizing Ashwagandha as therapy, especially clinical studies. Furthermore, to determine the benefits of Ashwagandha, more research is needed, primarily in the clinical setting, to verify the raw material's effectiveness. According to the research, Ashwagandha may be useful as a treatment, particularly for a variety of neurological conditions.²¹ Several randomized-controlled trials have reported stress-reducing and anxiolytic effects of standardized Ashwagandha extracts in humans. Although promising effects have been reported, current evidence remains heterogeneous and further large-scale clinical trials are required before definitive therapeutic conclusions can be drawn.

Female health, hormonal balance, and vitality. Asparagus racemosus is also known by the traditional names “Shatavari” and “who possesses a hundred husbands or acceptable to many.” In Ayurveda, it is considered a feminine tonic. In spite of its rejuvenating properties, this herb promotes libido, enhances ovulation and folliculogenesis, lowers inflammation in the sex organs and even lubricates their dry tissues, prepares the womb for conception, prevents miscarriages, and acts as a postpartum tonic by promoting lactation and postpartum uterine involution, and normalizing fluctuating hormones.²² Additionally, it is advised for leukorrhea and menorrhea. Shatavari is the main Ayurvedic tonic for females, and withania is the main one for males.²³ When administered over an extended period of time, root extracts did not result in any changes in the behavior of rats or mice, even at very high dosages. The plant is safe to use during pregnancy and while nursing. Since the majority of Shatavari-containing medications on the market are available in polyherbal formulations, it might be challenging to determine whether a given medical effect is exclusively attributable to the drug's Asparagus racemosus component.²⁴

Memory booster, cognitive support. Bacopa monnieri is a medicinal climbing perennial of the Scrophulariaceae family that is frequently utilized in the field of Ayurveda. Its leaves are tiny and rectangular, and its flowers range in color from white to purple (see Image: Bacopa). Other names for this herb include Brahmi, water hyssop, thyme-leaved gratiola, and the herb of grace. Brahmi is the Hindu legendary name for “Brahma,” the “supreme creator.” Brahmi can be Centella asiatica (Gotu kola), Bacopa monnieri, or a combination of the two herbs. Bacopa has been shown to improve verbal learning, memory acquisition, delayed word recall, cognitive function, and anxiety levels. Bacopa monnieri has numerous pharmacological properties, including bronchodilator, cardiotonic, anti-inflammatory, anticonvulsant, antioxidant, and peptic ulcer prophylaxis.²⁵ The antioxidant qualities of bacopa leaf powder are well established. Bacopa's ability to improve cognition is most likely due to bacosides, a class of saponins. Purified bacosides A and B, and an alcoholic extract from bacopa may enhance memory, learning ability, and cognitive function. Bacopa has been shown to prevent oxidative damage by lowering the amounts of the protein carbonyl in the cytoplasm and mitochondria of every part of the brain. It has been demonstrated that bacopa inhibits lipid peroxidation in the rat prefrontal cortex, striatum, and hippocampal regions. The antioxidant superoxide dismutase, which increases in reaction to oxidative stress, is the first line of defense against free radicals.²⁶ In one study, after receiving medication, superoxide dismutase activity in diabetic rats reverted to normal. This suggested that there was balance between the oxidant and antioxidant species. As rats experience oxidative stress, those with diabetes have far lower amounts of reduced glutathione than those without diabetes. Bacopa has been shown to increase low glutathione levels.

Antioxidant, immunity booster, skin rejuvenation. The fruits of the Phyllanthus emblica L. (often referred to as amla), a tree indigenous to India and Southeast Asia, are abundant in bioactive chemicals that may be studied in naturally occurring molecules with biological activity increases.²⁷ Thus, the goal of this review is to highlight the health-promoting qualities, nutritional value, and rich phytochemistry of amla. Scientific evidence indicates that polyphenols and vitamin C are vital components of fruits and other sections of the amla tree. Significant antioxidant activity is conferred by the rich composition of polyphenol and vitamin C, in addition to important in vivo effects like improved antioxidant status and activity of the endogenous antioxidant defense system. Other potential health benefits include antidiabetic and anti-hyperlipidemic qualities.²⁸ Amla's diverse phytochemical composition makes it a valuable source of chemicals with possible health advantages. Scientific evidence supports the establishment of an endogenous antioxidant defense system as well as the direct avoidance of oxidative processes, making the antioxidant effects (from the high polyphenol composition) a significant property. With the current level of evidence, it would seem reasonable to assume that amla components, primarily polyphenols, may serve as a source of active compounds to support health (e.g., improving antioxidant status in smokers and protecting the digestive tract against stressors) and for protection against the development of diseases (e.g., helping to regulate serum glucose and insulin levels).^29,30

Detoxifier, immunity enhancer. Giloy (Tinospora cordifolia) has been regarded as the most significant and powerful therapeutic herb in Ayurvedic scriptures. For millennia, Giloy leaves have been used to treat a variety of human illnesses.³¹ This review emphasizes how Giloy leaves can be utilized to create functional food products and the fact that they have immunomodulatory qualities. The phytochemical content of Giloy leaves and the mechanism behind their immunomodulatory impact are the main topics of the current review. Particular pathways that are highlighted include the NF-kB pathway and interleukin regulation. Giloy leaves have antioxidant properties and trigger immune response-induced cell death.³² Research has demonstrated the possibility of using Giloy leaves to combine ancient knowledge with contemporary functional food manufacture in a variety of value-added products, including beverages, biscuits, and herbal formulations. Numerous products that have been developed, modified, and enhanced from the traditional applications of Giloy leaves are currently on the market and can aid in the treatment of various illnesses as well as immunity-related conditions.³³ However, in order to improve its use and application, more research and studies are needed to comprehend the mechanisms of action, which can aid in understanding its effects, applications, and how it interacts with other substances and therapies. Active compounds found in Giloy leaves may be responsible for these advantages.³⁴ Modern goods offer convenient ways to incorporate Giloy into daily practices. It is important to understand that certain medications and Giloy leaves may interact and interfere with one another. Thus, before using Giloy-based products daily, we suggest consulting a healthcare provider.³⁵ Most pharmacological evidence for Tinospora cordifolia is derived from animal and experimental studies, with limited human clinical trials available.

Digestive health, longevity. Terminalia chebula Retz, also referred to as “Haritaki/Myrobalan,” has long been used in traditional medicine. Numerous traditional medical disciplines, including Unani, Tibbati, Ayurveda, and Siddha, have made substantial use of it to treat conditions like bleeding, digestive issues, as a liver tonic, as a carminative, for the treatment of dysentery, as an analgesic, as an anthelmintic, as an antibacterial, and for the treatment of skin conditions.³⁶ Several electronic databases were used to examine studies published between January 1996 and December 2021 on the pharmacological effects of T. chebula and its phytoconstituents.³⁷ The biological characteristics of T. chebula, such as its antioxidative, antiproliferative, antimicrobial, proapoptotic, anti-diabetic, anti-aging, hepatoprotective, anti-inflammatory, and antiepileptic effects, were discovered using a number of laboratory techniques over the aforementioned period. Additionally, it aids the metabolism of fats and carbohydrates, and inhibits endothelial dysfunction and atherogenesis.³⁸ Numerous scientific investigations have found that a variety of T. chebula components, including fruits, seeds, galls, and barks, contain important bioactive compounds such as chebulic acid, chebulinic acid, and chebulaginic acid. A range of solvent solutions, such as water, ethanol, methanol, chloroform, and ethyl acetate, were used to extract these components. These compounds also showed beneficial pharmacological properties. Chebulanin and chebulagic acid have similar anti-inflammatory, anti-aging, antioxidant, antidiabetic, and cardioprotective properties. Neutralization of the free radicals that damage tissue and are linked to numerous other illnesses could be one way to do this.³⁹

Metabolism booster, respiratory health. Piper longum, also referred to as “long-pepper” or “Pippali,” is a herbaceous vine or perennial shrub that is indigenous to the Indo-Malayan area. It is found in many tropical and subtropical areas, such as the Middle East, America, Sri Lanka, and the Indian subcontinent. The fruits are used as a traditional remedy for bronchitis, colds, coughs, snakebite, and scorpion stings, and they are also used as spices and preservatives in cooking. Bioactive phytochemicals such as alkaloids, flavonoids, esters, and steroids are present in the plant extracts. There are many health advantages of essential oils derived from the roots and fruits of Pippali; they have antimicrobial, antiparasitic, anti-inflammatory, analgesic, antioxidant, anticancer, neuro-pharmacological, anti-hyperglycemic, hepatoprotective, anti-hyperlipidemic, antiangiogenic, immunomodulatory, antiarthritic, anti-ulcer, anti-asthmatic, and cardioprotective effects, and are also used as anti-snake venom agents.⁴⁰ This review discusses P. longum's consumption, distribution, ethnobotany, phytochemistry, pharmacology, medicinal significance, health advantages, safety, and toxicity.

Respiratory and adrenal health support. Since the Former Han period, licorice, a shrub with more than 30 species, has been used medicinally in East China, Greece, Egypt, and the West. Its root preparations have been used to treat immunodeficiency, respiratory, liver, and throat infections, and TB. Screening these plants for novel chemicals is essential, since traditional medicines are increasingly being utilized to treat chronic illnesses. In order to serve as a resource for upcoming clinical and basic research, this study thoroughly examines the ethnopharmacological applications, phytochemistry, biological activity, clinical data, and toxicity of licorice. The main focus is on the molecular mechanism of licorice extracts and their four flavonoids, indicating that licorice may be a safe, natural substitute for existing treatments of newly developing illnesses.⁴¹

Stress reliever, cardiovascular health. The effect of tulsi extract on biochemical indicators in healthy individuals with no known immunological or biochemical problems was the focus of one investigation. In a double-blind, randomized-controlled trial, 24 healthy individuals received a placebo capsule or a 300 mg Tulsi extract for 4 weeks. Prior to, during, and following the intervention, blood samples were obtained. While other tests revealed no appreciable changes, the results indicated that in certain individuals with increased triglyceride and cholesterol levels, there was a marked reduction in the levels. In conclusion, Tulsi extract showed cardioprotective properties by considerably lowering the increased cholesterol levels of the group of individuals studied.^42,43

Kidney health, stamina, vitality. Concerns around synthetic drugs have led to increased use of traditional treatments. The annual herbaceous plant Tribulus terrestris L. has been widely used for a number of medical applications, including analgesic, immunomodulatory, aphrodisiac, anti-urolithic, absorption-enhancing, cardioprotective, antidiabetic, anti-inflammatory, hypolipidemic, neuroprotective, and anticancer effects. T. terrestris has recently been discovered to contain saponins and flavonoids, which have been shown to have liver-protective, testosterone-boosting, anti-inflammatory, anticancer, and anti-diabetic properties.⁴⁴ Additionally, T. terrestris reduces blood pressure, increases testosterone secretion, and protects the reproductive, urinary, and cardiovascular systems. Numerous illnesses in humans and animals have been demonstrated to be cured due to its strong bioactive components. The significance of this review for human and veterinary health—specifically, veterinary poultry health—is the main focus. As an aphrodisiac, it might potentially be utilized to cure reproduction issues in humans and animals.⁴⁵ The comparative evidence synthesis of major Rasayana herbs is summarized in Table 2.

Evidence strength was graded based on the study design, sample size, and availability of human clinical trials.

Although several Rasayana herbs demonstrate promising pharmacological and clinical effects, the available evidence remains heterogeneous. Many studies involve small sample sizes, short intervention durations, or preclinical models. Therefore, the therapeutic potential of these herbs should be interpreted with caution until supported by larger, well-designed randomized clinical trials.

Rasayana is an essential part of Ayurveda, a system of ancient medicine that promotes health and rejuvenation. It aims to improve Rasa, the nourishing fluid produced after digestion, with nutrients, which leads to increased longevity, memory, intelligence, and a robust immune system; it also promotes mental wellness, promoting a youthful appearance and vitality; and is based on the principles of enhancing the body's dhatus, which are crucial for optimal health and disease prevention. Rasayana therapy is especially important for boosting immunity, also known as Vyadhikshamatava, which emphasizes the body's ability to resist diseases and maintain health. Immunity is influenced by genetics, environmental factors, and life choices. It not only strengthens immunity against diseases but also reverses disease processes, highlighting its crucial role in maintaining overall health.⁴⁸

Ayurvedic medicine's Rasayana focuses on reviving the body and strengthening its resilience, especially for neurological and cognitive systems. The effectiveness of several Rasayana plants has been investigated scientifically in the following areas.⁴⁹

Improvement of Cognitive Function: Enhancement of Memory and Learning: Research has demonstrated that Bacopa monnieri, also known as Brahmi, improves memory and cognitive abilities. Neurogenesis and Synaptic Plasticity: Centella asiatica, also known as Mandukaparni, is known to have neuroprotective qualities that promote synaptic connection and neuronal development. Neuroprotection, Anti-Aging, and Neurodegenerative Disease Prevention: Withania somnifera, often known as Ashwagandha, has shown promise in preserving neurons, which lowers the risk of developing neurodegenerative diseases.⁵⁰

Reduction of Oxidative Stress: Antioxidant qualities found in Rasayana plants help fight oxidative stress, which is a major contributor to neurodegeneration.

Mood-enhancing and anxiolytic effects: Stress and Anxiety Reduction: Ashwagandha, or Withania somnifera, is known for its adaptogenic qualities, which help with reduction of anxiety and stress. Mood Enhancement: Bacopa monnieri, often known as Brahmi, has been linked to enhanced mood and cognitive function. Improved Nervous System Performance.

Neurotransmitter Modulation: Shankhapushpi, or Convolvulus pluricaulis, affects neurotransmitter levels, which are necessary for stable emotions and the best possible brain function. Support for Nerve Regeneration: Ashwagandha, or Withania somnifera, helps to strengthen neural connections and heal damaged nerves. Resilience of the Mind Under Long-Term Stress. Protection From Stress-Induced Damage: Adaptogenic herbs, such as Ashwagandha (Withania somnifera), increase the body's resistance to stress and reduce its detrimental effects on cognitive processes.⁵¹

Rasayana therapy in Ayurveda is known for its anti-aging and longevity benefits. It promotes cellular regeneration and repair, reducing the effects of aging at the molecular level. Rasayana herbs are traditionally associated with longevity and rejuvenation. Experimental studies suggest antioxidant and cellular protective mechanisms that may contribute to healthy aging; however, strong clinical evidence in humans remains limited. Rasayanas are also strong antioxidants that prevent oxidative stress, neutralize free radicals, and shield cells from harm. These characteristics postpone the onset of degenerative diseases associated with aging. In experimental studies, some Rasayana herbs have demonstrated neuroprotective effects, which may support cognitive health. However, further clinical research is required to confirm these effects in humans. As people age, Gotu kola and Ashwagandha help preserve cognitive function by reducing cortisol-induced neuronal damage and maintaining brain plasticity. The immune system is strengthened through herbs like Guduchi and Amla, improving immune resilience and reducing chronic inflammation. Rasayanas also regulate hormonal balance, supporting skin elasticity, bone health, and overall vitality. The cardiovascular system benefits from herbs like Arjuna, which supports heart health and vascular function. Rasayanas act as adaptogens, enhancing the body's resilience to stress and improving sleep quality, contributing to longevity and youthfulness. Most anti-aging and neuroprotective claims are based on experimental or small clinical studies; therefore, therapeutic recommendations cannot be made at present.

Rasayana is a comprehensive strategy for enhancing metabolic efficiency, food absorption, and digestive function. Ginger, Ajwain, Cumin, Ashwagandha, Guduchi, Shatavari, Fenugreek, Amla, Turmeric, Triphala, Neem, Arjuna, and Ashwagandha are among the many herbs that are part of Rasayana treatment. Ajwain promotes gastric secretion, cumin promotes gastric secretion, and ginger activates digestive enzymes. Ashwagandha promotes thyroid function, controls the metabolic rate, and guards against metabolic diseases. Guduchi increases fat metabolism, detoxification, and liver function. Shatavari helps control weight and improve metabolic efficiency by balancing hormones. Amla lowers blood sugar and aids with digestion, whereas fenugreek regulates blood sugar and insulin sensitivity. Anti-inflammatory herbs like ginger and turmeric reduce chronic inflammation, while Rasayana plants support cardiovascular and gastrointestinal health, and aid detoxification.

In Ayurveda, Rasayana treatment uses herbal and nutritional preparations to increase the lifespan and regeneration, and prevent illness. It is essential to follow a balanced diet that includes seasonal, organic, and fresh foods. Certain nutritional formulations, such as Madhu Rasayana, Phala Rasayana, Ghrita Rasayana, and Ksheer Rasayana, improve digestion, immunity, and vigor. Simple rice gruels aid in nutrition and digestion. Herbal preparations like Medhya Rasayana herbs, including Ashwagandha, Shankhpushpi, and Brahmi, improve immunity, lower stress, improve cognitive function, support lifespan and detoxification, and improve reproductive health.⁵² These therapies increase the lifespan and disease resistance, and promote good health when combined with a disciplined lifestyle, enough sleep, and stress management.

Rasayana therapy in Ayurveda emphasizes not only dietary and herbal interventions but also a disciplined lifestyle to promote longevity, immunity, and overall well-being. A structured daily routine (Dinacharya) is essential, including waking up early during Brahma Muhurta, practicing oral hygiene with oil pulling and tongue scraping, engaging in Abhyanga (oil massage), performing yoga, and practicing meditation to maintain mental clarity and physical vitality. Seasonal regimens (Ritucharya) help adjust the diet and habits according to changing climates, such as consuming nourishing foods in winter, detoxifying in spring, and staying hydrated in summer. Behavioral guidelines (Sadvritta) ensure mental and social harmony, advocating for emotional balance, truthfulness, respect, and regulated sleep. Achara Rasayana further emphasizes a moral and ethical lifestyle, discouraging addictions, promoting celibacy for energy conservation, and encouraging selfless service and charity.⁵³ Furthermore, the restorative benefits of Rasayana therapy are amplified by periodic detoxification using Panchakarma treatments, including Vamana (therapeutic emesis), Virechana (purgation), Basti (medicated enema), Nasya (nasal cleaning), and Raktamokshana (bloodletting). By integrating these lifestyle recommendations, Ayurveda aims to achieve a balanced state of physical, mental, and emotional health, ultimately leading to enhanced vitality and longevity.

Panchakarma is a comprehensive detoxification method in Ayurveda, focusing on purifying the body, rejuvenating tissues, and restoring balance to the doshas (Vata, Pitta, and Kapha). Vamana (therapeutic emesis), Virechana (purgation), Basti (medicated enema), Nasya (nasal treatment), and Raktamokshana (bloodletting) are the five main cleaning techniques. These treatments aid the removal of built-up toxins, strengthen immunity, improve digestion, and increase the lifespan. Vamana is used for Kapha-related disorders, while Virechana detoxifies the liver and balances Pitta. Basti is vital for Vata disorders, while Nasya clears toxins and improves cognitive functions. Raktamokshana purifies the blood and is beneficial for skin disorders and inflammatory conditions.⁵⁴ When combined with preparatory and post-detoxification regimens, Panchakarma enhances tissue regeneration and strengthens the body's resistance against diseases.

Although Rasayana herbs demonstrate promising pharmacological activities, ensuring consistent product quality remains a major challenge. Herbal preparations often vary in phytochemical composition depending on

For example, the concentration of withanolides in Withania somnifera or bacosides in Bacopa monnieri may significantly differ across commercial formulations. Such variability directly influences therapeutic efficacy and safety.⁵⁵

Standardization should therefore include

Without rigorous standardization, the reproducibility of clinical outcomes remains uncertain, limiting integration into evidence-based medicine.⁵⁶ Authentication of herbal raw materials should involve multiple analytical approaches, including macroscopic and microscopic identification, phytochemical fingerprinting using HPTLC, HPLC, or LC-MS, and where applicable, DNA barcoding techniques to confirm botanical identity. Authentication of Rasayana herbs should involve multiple complementary approaches. Macroscopic and microscopic evaluation can be used to identify diagnostic morphological characteristics of crude drugs. Chromatographic techniques such as HPTLC and HPLC allow quantification of marker compounds, including withanolides in Withania somnifera and bacosides in Bacopa monnieri. Advanced analytical techniques such as LC–MS provide detailed phytochemical profiling, while DNA barcoding can confirm botanical identity and detect adulteration, particularly in cases where morphologically similar species are substituted. Batch-to-batch variability has been reported in commercial herbal products. For example, significant variation in withanolide content has been observed among different commercial preparations of Withania somnifera. Similarly, bacoside concentrations in Bacopa monnieri products may differ depending on extraction methods and raw material quality. Such variability may influence therapeutic outcomes, and highlights the importance of standardized extracts and quality control testing. Quantitative variability has been documented in commercial herbal preparations. Standardized extracts of Withania somnifera generally contain 2%–10% total withanolides, whereas commercial products have shown variability ranging from approximately 0.3% to 8.5%. Similarly, Bacopa monnieri extracts are commonly standardized to 20%–55% bacosides, but marketed formulations may contain about 5%–50% bacosides depending on the raw material quality and the extraction method. Such variability may influence therapeutic outcomes and reproducibility. Authentication should therefore include macroscopic and microscopic identification, phytochemical fingerprinting using HPTLC, quantitative analysis by HPLC, and advanced metabolite profiling using LC–MS. DNA barcoding (ITS, rbcL, and matK) may further confirm botanical identity and detect adulteration, particularly in Bacopa monnieri substituted with Centella asiatica. Integration of these approaches ensures batch-to-batch consistency and improves the reliability of Rasayana herbal products. For example, the concentration of withanolides in Withania somnifera or bacosides in Bacopa monnieri may significantly differ across commercial formulations. Reported batch-to-batch variability is substantial. Commercial Withania somnifera products have shown approximately 0.3%–8.5% withanolides, whereas standardized extracts typically contain 2%–10% total withanolides. Similarly, marketed Bacopa monnieri formulations may contain approximately 5%–50% bacosides, while standardized extracts commonly contain 20%–55% bacosides. Authentication should include macroscopic and microscopic identification, HPTLC/HPLC fingerprinting, LC-MS profiling, and, where feasible, DNA barcoding to detect adulteration or species substitution.

One of the most serious concerns in herbal medicine is adulteration and contamination.

Regulation of Ayurvedic and Rasayana products varies globally:

Key regulatory challenges include the following:

While traditional usage provides historical credibility, modern regulatory frameworks increasingly demand

To enhance global acceptance, Rasayana products must meet international quality, safety, and efficacy standards comparable to those of conventional pharmaceuticals. Manufacturing of Ayurvedic herbal products should comply with good manufacturing practices (GMP) to ensure product quality, safety, and batch-to-batch consistency. Post-marketing monitoring through pharmacovigilance systems is also essential. In India, safety monitoring is supported by the AYUSH pharmacovigilance program, while in the United States, herbal products are regulated under the Dietary Supplement Health and Education Act (DSHEA). In Europe, traditional herbal medicines are regulated through the Traditional Herbal Medicinal Products Directive (THMPD). In India, post-marketing surveillance of Ayurvedic medicines is supported through the Ministry of AYUSH Pharmacovigilance Programme, which collects and evaluates adverse drug reaction reports for traditional medicines.

A substantial portion of the pharmacological evidence described in this review is derived from

While these studies provide mechanistic insights (antioxidant activity, NF-κB modulation, neuroprotection, and immunomodulation), several limitations exist.

Most clinical evidence consists of small-sample studies with short durations.

Therefore, while preclinical data support mechanistic plausibility, robust multicenter randomized-controlled trials are necessary before definitive therapeutic claims can be made.

To bridge traditional knowledge and modern medicine, future research should focus on the following:

Integration of pharmacognosy, phytochemistry, molecular pharmacology, and clinical medicine will strengthen the scientific foundation of Rasayana therapy.

Evidence for Rasayana therapy is derived from both single-herb studies and classical polyherbal formulations such as Chyawanprash and Triphala. While several single herbs like Withania somnifera and Bacopa monnieri have been evaluated in controlled studies, many traditional formulations contain multiple components that may act synergistically. This complexity makes attribution of specific pharmacological effects to individual herbs difficult. Furthermore, variability in formulation composition, dosage, and preparation methods contributes to heterogeneity in clinical outcomes. Therefore, results from single-herb studies should not be directly extrapolated to classical polyherbal preparations, and cautious interpretation is required.

1. Tinospora cordifolia (Guduchi)

While Guduchi is widely recognized for immunomodulatory benefits, recent case reports have linked its consumption to herb-induced liver injury (HILI), particularly in patients with pre-existing autoimmune disorders. Excessive immune stimulation may exacerbate autoimmune hepatitis in susceptible individuals. Therefore, caution is advised in patients with autoimmune conditions or underlying liver disease. Several clinical case reports have documented Tinospora cordifolia -associated herb-induced liver injury (HILI), particularly in individuals with autoimmune predisposition. A case series reported acute liver injury in patients consuming Giloy-based herbal preparations during the COVID-19 period. It is important to distinguish Tinospora cordifolia from Tinospora crispa, as pharmacological and safety data differ between species. Evidence from Tinospora crispa should not be extrapolated to Tinospora cordifolia due to differences in phytochemical composition and reported toxicity profiles.

2. Glycyrrhiza glabra (Mulethi/Licorice)

Chronic consumption of licorice may cause pseudoaldosteronism due to glycyrrhizin-mediated inhibition of 11β-hydroxysteroid dehydrogenase type 2. Reported effects include the following:

Licorice should be avoided in patients with uncontrolled hypertension, renal disorders, and cardiovascular disease, or those receiving diuretics and corticosteroids. Clinical reports have documented licorice-induced pseudoaldosteronism, characterized by hypertension, hypokalemia, and sodium retention, due to inhibition of 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD2) by glycyrrhizin. Pseudoaldosteronism has been reported with chronic glycyrrhizin intake typically exceeding 100 mg/day, particularly with prolonged consumption. Regulatory authorities recommend limiting daily glycyrrhizin intake to lower levels to minimize the risk of hypertension, hypokalemia, and fluid retention. Clinical reports suggest that pseudoaldosteronism is more likely with chronic glycyrrhizin intake exceeding approximately 100 mg/day, particularly during long-term consumption. Therefore, regulatory authorities recommend limiting daily glycyrrhizin exposure to minimize the risk of hypertension and hypokalemia.

3. Piper longum (Pippali)

Piperine, the major alkaloid in Pippali, is a known inhibitor of CYP3A4 and P-glycoprotein. It may significantly alter the bioavailability of co-administered drugs, including:

Therefore, concurrent use with narrow therapeutic index drugs requires caution. Piperine has been shown to inhibit CYP3A4 and P-glycoprotein in vitro and in vivo, with reported enhancement of drug bioavailability ranging from approximately 30%–200% depending on the co-administered drug and dose. This variability highlights the need for caution when used alongside medications with a narrow therapeutic index. Piperine-mediated enhancement of drug bioavailability has been reported to range from approximately 30%–200%, depending on the co-administered drug and dose. This variability highlights the need for caution when used alongside medications with a narrow therapeutic index.

4. Withania somnifera (Ashwagandha)

Generally well tolerated, but reported adverse effects include:

Caution is advised in patients with hyperthyroidism or those on thyroid medications. Piperine has been shown to inhibit CYP3A4 enzymes and P-glycoprotein transporters, which may increase the bioavailability of several drugs, including phenytoin, rifampicin, and certain chemotherapeutic agents. Standardized extracts of Withania somnifera commonly contain 2%–10% withanolides, while Bacopa monnieri extracts are typically standardized to 20%–55% bacosides. Variability outside these ranges may affect both efficacy and safety outcomes. It is important to clearly distinguish Tinospora cordifolia from Tinospora crispa, as cases of hepatotoxicity reported in the literature are often associated with Tinospora crispa. Misidentification or substitution between these species may lead to incorrect safety interpretation; therefore, species-level authentication using pharmacognostic and molecular methods is recommended. Importantly, safety findings reported for Tinospora crispa should not be directly extrapolated to Tinospora cordifolia, as both species differ phytochemically and toxicologically.

Potential pharmacokinetic and pharmacodynamic interactions include:

Given increasing polypharmacy in modern populations, systematic herb–drug interaction studies are warranted.

Safety outcomes depend on:

Most adverse reports are associated with:

While Rasayana herbs demonstrate promising pharmacological potential, therapeutic claims should be interpreted with caution until supported by large-scale, well-controlled clinical trials with rigorous safety monitoring.⁵⁸