# Kṣārakarma (Therapeutic Alkali Application) > Kṣārakarma is the clinical application of kṣāra, a caustic alkali made from plant ash, to tissue; in fistula-in-ano it takes the form of a medicated thread, kṣāra-sūtra. Suśruta devotes a whole chapter to preparing it, and warns it is more to be feared than fire in untrained hands. ## Key facts - **Sanskrit name:** Kṣārakarma ## What it is Kṣārakarma is the application of kṣāra, a caustic alkali obtained from plant ash, to living tissue. The source record glosses it as "therapeutic alkali application" and files it under kriyā-bāhya, the external procedures, at practitioner level vaidya-only. This is surgical work. It is not a treatment a reader can arrange for themselves, and nothing on this page is a method. ## Where it comes from in the classical literature Suśruta Sūtrasthāna 11, the Kṣāra-paka-vidhi chapter, is the classical chapter on kṣāra, and the record cites it correctly. In Bhishagratna's translation the chapter sets out the preparation: selected plants and limestone are burnt to ash, the ash is dissolved in water or cow's urine, the liquid is filtered twenty-one times, then boiled down, with further additives producing a mild, middling or strong grade. Apāmārga and Snuhī both appear in the chapter's list of plant sources, alongside Kutaja, Palāśa, Arka, Pāṭalā and others. The same chapter carries the line most often quoted about this procedure: "An Alkali administered by an ignorant physician is to be dreaded more than poison, fire, blows with a weapon, thunder-bolts, or death itself; while in the hand of an intelligent physician it is potent enough to speedily subdue all serious diseases in which its use is indicated." The fistula application the record describes belongs to a different chapter. Suśruta Cikitsāsthāna 8, Bhagandara Cikitsitam, is the chapter on fistula-in-ano, and its text has kṣāra, or alternatively agni, applied at the fistula opening. ## What it involves The record gives three steps, and no more: - kṣāra of Apāmārga or Snuhī is prepared following the Suśruta Sūtrasthāna method - for bhagandara, a kṣāra-sūtra is threaded through the fistula tract - the thread is replaced weekly until the tract closes Afterwards the record specifies a local Triphalā-water dressing, with antibacterial coverage as needed. The record gives no course length, no frequency beyond the weekly thread change, no season, and no adverse-event data. ## What is used The dravyas named in the record are Apāmārga, Snuhī (as the kṣāra source) and Yavakṣāra. Triphalā water is named for the dressing. No oils are named. ## Why it needs a vaidya Kṣāra is a caustic. It works by destroying tissue at the point of contact, and the classical text is explicit that its grade, quantity and site are the whole of the skill. Kṣāra-sūtra in a fistula is a staged surgical procedure with a wound that must be dressed and watched between thread changes, which is why the record pairs it with antibacterial coverage. Suśruta's own warning is the plainest statement of the risk, and it is quoted above. This is not something to attempt, improvise or source materials for. --- Canonical version of this page: https://nighantu.ageayurveda.com/practice/ksharakarma/ Published by Age Ayurveda in the Nighantu. Educational reference only, not medical advice. Incorporates material from the Amidha Ayurveda Herb Database under CC BY 4.0.