The term Ashtanga Hridaya literally means the heart of eight organs (of Ayurveda). Asthangahridaya tells what you can find in this great Ayurvedic classic by Vagbhata, written in the fifth century AD.

 “kaya-bala-grihordhwanga
 salya-damsthra-jaravrishan
 ashtanganithasyahu
 schikitsayeshu samsritha”

The above slogan tells that kaya chikitsa (treating physique or body), bala (baala) chikitsa (pediatrics), griha chikitsa (psychiatry), urdhvanga chikitsa or shalakya tantra (eye, ear, nose and parts above neck), salya tantra (surgery), damsthra chikitsa (toxicology) and jara chikitsa or rasayana chikitsa (rejuvenation therapy), vrishya chikitsa or vajeekarana chikitsa (aphrodisiac therapy) are the eight branches or organs (angas) of Ayurveda.

Ashtanga hridaya is the book that tells in detail about all the eight angas of Ayurveda. It is the sum total of all knowledge spread across millions of slogas from thousands of books written by eminent Ayurveda practitioners and teachers from the past. All topics regarding Ayurveda are concentrated to some 7000 slogas in Ashtangahridaya.

Ashtanga vaidyas of Kerala learned and practiced all of the eight branches of Ayurveda. There are different vaidya families that concentrated on specific angas only. Pampinmeykkattu family is still known for damsthra chikitsa, mainly treating snake venom related conditions.

Astagahridaya tells in detail about dinacharyas (daily routine), ritucharyas (seasonal routines) etc. Ritucharya is the method of adjusting our daily activities like taking bath, food and drinks, work and travel, entertainment, rest and sleep etc. It also details the methods of controlling our thoughts, words, action, and even what we look at and see.

There is a sloga in Ashtangahridaya, which we can regard as the corner stone of health;
 Nityam hithahara vihara sevii
 Sameekshyakaree vishayeshuasakthaha
 Datha samassthya paraha kshamava
 Napthopaseveecha, bhavatya rogaha

The meaning of the sloga goes like this –
Take good food, do moderate physical exercise, think well before starting risky ventures, live a life of self respect, give alms according to your capacity, love all alike, tell only truth, maintain composure under pressure, be forgiving, mingle with good people –

The brief sloga tells about the ingredients of good physical and mental health. Deviating from this lifestyle can cause diseases.

The Reliability of Ashtangahridaya
Vagbhata Acharya, in the concluding part of Ashtangahridaya inscribes a sloga as follows.

 Idamagamasidhathwal
 Prathyakshaphaladarsanal
 Manthraval Samprayokthavyam
 Na Meemamsyam Kadhanjana

The translation goes like this – this much (the scripts of ashtangahridaya till this point) is an accumulation of memories from past experiences. Practicing them will give scalable results. Continuously recite this as a mantra. Thus, you will get the powers and you can utilize this knowledge with confidence.

Ashtangahridayam indeed is the concentrated form of all knowledge of practitioners of Ayurveda till the time of Vagbhata. All the knowledge in Ashtangahridaya is in highly processed (samskrita) form. One can be said to be a vaidya if he has this knowledge.

No one can prove even a word in Ashtangahridaya untrue. It not only have the treatment methods, medicines, etc listed, but also the lifestyle requirements, the root-cause of diseases, etc are all true according to the uncountable Ayurvedic practitioners that bear witness to the effectiveness of Ayurveda.

Charaka samhita is the main Ayurvedic text that deals with medicines and non-surgical methods of Ayurvedic treatment. Charaka Acharya lived in third or second century BC. Charaka Samhita is one of the three major classics of Ayurveda. Sushruta Samhita and Ashtanga Hridayam being the other two.

Charaka compiled the work of a student of Athreya Acharya, Agnivesha on general medicine, which was mainly the teachings of the Acharya.

Just like most ancient Ayurvedic scripts, Charaka Samhita too is in poetic form, mainly to facilitate easy memory by the students. It generally discusses kaya chikitsa, one anga (branch) of Ashtanga Ayurveda.

Charaka Samhita treats life as a form of consciousness and knowledge. Charaka Samhita (charaka samhitha, charaka samhidha, etc) tells in detail about health, hygiene, diet, lifestyle and medicine. Snehan and Swedan karmas are also described in detail. It also has directions about the method of constructing a vaidya sala (hospital).

Charaka samhita tells about the root causes of diseases, diagnosis of diseases and treatment of different diseases. Human anatomy, sense organs, physiology, panchakarma, etc.

Charaka samhita has a typical slogan which tells that a person has better chance of survival if he is hit by lightning than if he is treated by a fake vaidya (Ayurvedic practitioner).

Bhavaprakasa by Bhava Minsra is believed to be written in 16th century AD.

Bhava minsra (also Bhava Misra, Bhava minsara, Bhava Minshara) describes in detail the basic concepts of Ayurveda. It tells about healthy living, causes of diseases, symptoms of diseases, and cure of all diseases. It also tells about preparation of medicines from plants, animal products and minerals.

An Ayurveda practitioner must be open to new ideas. Bhavaminsra describes about medicines from outside India. It is also the comprehensive source for accurate information about the origin of Ayurveda in India. The origin and development of India was in a systematic manner till the time of Bhavminsara. Foreign invasions caused the ruin of this science of life in the 16th and 17th century, which saw a revival in 18th and 19th centuries.

Sarngadhara Samhita is a practical handbook for Ayurveda practitioners. It is regarded as one among the top six ancient scripts of Ayurveda. While Sushruta samhita, Charaka Samhita and Ashtangahridaya are considered the major triad of Ayurveda, Sarngadhara Samhita, Madhavanidana and Bhavaprakasha are considered the minor triad.

In Sharngadhara Samhita, Acharya Sharngadhara make deliberate attempts to make the language simple and easily understandable. He also omitted a lot of details, mainly due to the spread of the major triad of Ayurveda classic writings. It is believed that the book was written in the 15th century.

The book is divided into three sections.

The first section (prathama khanda) of the book tells in detail about the weights and measurements, time and place to collect herbs, the effect of seasons on the quality of herbs, methods of diagnosis, human anatomy and physiology, human constitution (dosha types), appropriate food and diet, etc. Diagnosis of condition by studying pulse is described in detail.

The middle section (madhyama khanda) describes the methods of preparation and mixing of herbal extracts to make medicines. The mixing methods of fresh juices, hot and cold infusion, mixing of powders (choornas), preparation of Gulika (gutika-pills), oils, ghee, arishta, dhatusudhi or purification of metals or minerals and Rasa (medicines with mercury).

The last section (uttara khanda) describes in detail all the five karmas of panchakarma – sneha, swedan, vaman, virechan and basti. It describes different kinds of basti (enema).

Sarngadhara samhita is also spelt – sarngadhara samhitha, sarngadara samhita, sarngadara samhitha, sarangadara samhita, sarangadhara samhitha, etc.; – accurate spelling is pending.

Madhava Nidana or Madhava Nidanam is an ancient book that comments to some extent on Sushruta samhita, Charaka samhita and Astangahridaya. It doesnÂ’t tell in detail about treatment options by tells clearly about different diseases and deals with kaya chikitsa, bala chikitsa, shalya tantra, damstra chikitsa and shalakya chikitsa.

Sushruta samhita written some 3000 years ago by an ancient acharya of Ayurveda, Sushruta is regarded as the basic knowledge of surgery. Sushrutha was a great surgeon of ancient times. It is also regarded as one of the four principal books on surgery. In his book, sushrutha samhitha, he also describes the methods of Panchakarma.

Surgery is an anga (branch) of Ashtanga (eight-branched) Ayurveda and is named Shalya Tantra or Shalakya Tantra.

Dhanvatary, who is considered the god of medicine and surgery is believed to hand over the knowledge of surgery to Sushruta. In the ancient times, physicians practicing surgery were known as Dhanwantareyans, because of their perceived connection with Lord Dhanwantary.

SushrutaÂ’s main forte is plastic surgery. His description of procedures of plastic surgery in this ancient book closely follows suite with modern plastic surgery procedures.

Sushruta says there are 76 conditions that affect eyes. He prescribes accurate surgical methods for 51 of them.

Sushruta also describes the sastras (weapons) to use for surgery. The weapons are sharp, with long handles and have striking similarities with modern surgical equipments. He lists weapons to make deep but sharply targeted cuts, remove or replace tiny parts, needles to sew severed flesh and muscles together, etc. He also suggests hygienically cleansing the room, weapons, hands of the surgeons, etc by smoking appropriate herbs, washing the weapons in boiled water and with appropriate herbal additions.

The Indian names of surgery is sastrakriya or sastra karma. Both means an action with a weapon.

Sushruta recommends surgery only for situations where medicines are incapable of curing the condition.

In addition to details of surgery, Sushruta Samhita also describes more than a thousand diseases and conditions, problems associated with aging and mental illnesses.

He also tells in detail about prasoothi tantra or Ayurvedic midwifery.

Sushruta Samhita lists 700 medicinal herbs. He also tells the methods of preparation of medicines.

Sushruta Samhita is spelt in many different forms. A few among them are susrutha samhitha, sushrutha samhitha, susruta samhita, sushruda samhida, susruda samhida, susrudha samhidha, etc.

Astanga Samgraha, written by an Ayurveda acharya named Vagbhata in 6th century AD is the compilation of the works by both Charaka (Charaka Samhita) and Sushruta (Sushruta Samhita). Vagbhata later concentrated Astanga Samgraha to a new book Ashtangahridya (ashtanga hridaya). The essence of Ashtanga Samgraha is visible in Astanga hridaya).

Another difference between Ashtanga Hridaya and Ashtanga Samgraha is that the former is written in prose and the latter in poetic (verse) form. There are also doubts whether the two are written by the same person or by two different persons with the same name.

Ashtanga means eight branches and samgraha means compilation in concentrated (abstract) form.

Ashtanga Samhita, ashtanga samhitha, etc also refer to astanga samgraha.