Ashtavaidyans are believed to be the traditional Ayurvedic physicians of Kerala and are from Namboothiri community. They are masters of the eight branches of medicine from which the word Ashtavaidyan is originated. They wrote several books incorporating their observations and clinical experiences. "Chikitsa Manjari", "Yogamithram", "Abhidhana Manjari", "Alathur Manipravalam", "Sindoora Manjari" and "Kairaly Commentary on Ashtanga Hridayam" are some of them. They come under the family of Vaagbhatachaaryan, one of the members of Brihat Trayee. Brihat Trayees are three authentic Aachaaryans, namely Susruthan, Charakan and Vaagbhatan.

According to Mr. N V K Varier's "Ayurveda Charithram", the word Ashtavaidyans does not refer to eight designated families of physicians, but rather to 18 Ashtaangavaidyans each one designated to 18 Sabhaamadhams (Vedam Schools) serving the many (32) Graamams of Kerala. These families were learned experts proficient in all the eight branches (Ashtaangams) of Ayurveda system (Poorna Vaidyans or complete physicians). The word Ashtaangavaidyans were later apparently reduced to Ashtavaidyans. It so happens that, in the absence of male members, several of these families had to be finally merged into eight of these families. The families are listed below with the existing families in the left column. Except Aalathiyoor and Kaarathol who are Nambis, all others are Moosses.

1.	Aalathiyoor Nambi	1. Aalathiyoor Nambi 2. Kaarathol Nambi 3. Choondal Mooss
2.	Elayidath Thaikkatt Mooss	4. Elayidath Thaikkatt Mooss 5. Kuriyedath Mooss (Njarakkal Mooss) 6. Kurumbempilly Mooss 7. Paduthol Mooss
3.	Pazhanellippurath Thaikkatt Mooss	8. Pazhanellippurath Thaikkatt Mooss 9. Peringavu Mooss 10. Parappur Mooss
4.	Kuttancherry Mooss	11. Kuttancherry Mooss 12. Vatuthala Mooss 13. Akalaanath Mooss
5.	Vayaskara Mooss	14. Vayaskara Mooss
6.	Chirattamon Mooss	15. Chirattamon Mooss (Olassa Mooss)
7.	Velluttu Mooss	16. Velluttu Mooss 17. Ubhayur Mooss
8.	Pulamanthol Mooss	18. Pulamanthol Mooss

Of these, Kaarathol Nambi either became extinct without any male children, or became Vaidyamadham. Moreover, there are no practising physicians in the families of Kuttancherry, Vayaskara and Velluttu Mooss, at present.

Another version is that it was Lord Parasuraman who brought Brahmanans (Namboothiris) to Kerala, assigned eight of the families as physicians, and these families came to be known as Ashtavaidyans. There is a third view which states that eight prominent disciples of Vaagbhata and their families continued the Ashtaangahridayam method of treatment, thus prompting the dual meaning of the word. Some believe that Vaagbhata came to Kerala and composed Ashtaangahridayam sitting on a rock near Thiruvizha temple, though historians contest this. Anyway, while the rest of the country follows Charaka and Sushrutha, Kerala follows Vaagbhata's Ashtaangahridayam, and this strict method of treatment is world-renowned.

As mentioned earlier, all the families are addressed as Moosses rather than Namboothiris, except Aalathiyoor and Kaarathol who are called Nambis. Ashtavaidyans are given a slightly depressed status perhaps because they have to examine dead bodies, perform surgical operations and use and follow Budhist Granthams (Treatises). However, considerable respect and place are given to them by the Namboothiri community.

Owing to the slightly lower status for Moosses, they are not permitted inside Yaaga saalaas, a place where Yaagams are performed. It is, however essential to have a physician nearby. This was assigned to Vaidyamadham. It is likely that Kaarathol Nambis were upgraded to Namboothiris and brought to Mezhathol for this purpose. Vaidyamadham was said to be the physician for all the 99 Yaagams performed by Mezhathol Agnihothri. The family follows Aalathiyoor Nambi's treatment methods, which points to the possibility of his ancestry to Kaarathol Nambi, who was himself trained under Aalathiyoor Nambi.

There are not many historical studies nor records documenting this rich heritage. Their knowledge, ideas, experiences and ideals will be of great value not only to the present generation, but also to the future ones to come. Kerala is in a way fortunate to have had a number of people taught and trained by the Ashtavaidyans. The heritage has even transgressed to other communities and religious faiths.