Karpasa Moola (Cotton Root): Benefits, Evidence & Safety

TL;DR

Karpasa moola is the root (root bark) of the cotton plant, Gossypium herbaceum, described in Charaka Samhita as pungent and heating, pacifying Vata and Pitta. Historical Western practice used it as a uterine stimulant, and its root bark contains gossypol. Modern efficacy research on the root is essentially absent. (49 words. Sources: Caraka Samhita online; LactMed; Ellingwood 1902.)

What it is

Karpasa moola is the root, specifically the root bark, of Gossypium herbaceum L., the cotton plant of the Malvaceae family. The Sanskrit name Karpasa covers the whole plant, but moola specifies the root drug, distinct from the seed (karpasa beeja) and the seed oil. The Charaka Samhita research database describes the root bark's Ayurvedic properties as: pungent (katu) in taste, hot (ushna) in potency, pungent (katu) in post-digestive effect, light (laghu) and sharp (tikshna) in quality, with the action of pacifying Vata and Pitta. (Karpasa: Carak Samhita)

Traditional use

Charaka Samhita references Karpasa three times: as an external paste (lepa) for Kushtha (skin disorders) at Chikitsa Sthana 7/96, as an ingredient of a dhumapana (medicated-smoke) preparation at 18/75, and, most relevant here, as an ingredient of Karpasmooladi yoga at Chikitsa Sthana 26/69, a formulation built around the cotton root. The root is also the karpasa in Karpasasthyadi taila, the classical medicated oil. These are traditional references, not clinical proof. (Karpasa: Carak Samhita)

In Western herbal history, cotton root bark had a parallel reputation: Ellingwood's 1902 materia medica records it as an emmenagogue and parturient that "produces firm, regular and strong uterine contractions," used historically for suppression of menses and uterine inertia, and it was listed in the U.S. dispensatory tradition. A modern review of uterotonic plants notes cotton root bark among the traditional remedies receiving renewed attention from midwives for applications during pregnancy and labour. (Ellingwood, Materia Medica, 1902; Uterotonic plants review, PMC)

What modern research says

Gossypol content and reported effects (constituent-level data)

The NIH's LactMed (Drugs and Lactation Database) records that Gossypium herbaceum root bark and seeds contain gossypol, and lists gossypol's reported adverse effects: hypokalemia (low blood potassium), mild leukopenia and thrombocytopenia, fatigue, dry mouth, dry skin, and gastrointestinal upset. LactMed also notes that Gossypium is a "purported galactogogue" but that "clinical trials supporting these uses are small and inadequate to validate its efficacy." This is constituent and safety information, not evidence the root works as a medicine. (LactMed: Gossypium, NCBI)

Quality-standard research on the root (not efficacy)

A pharmacognostic study of three karpasa root samples (Int. J. Food and Nutritional Sciences) established identity and purity parameters: macroscopic and microscopic examination, HPTLC fingerprinting, and physicochemical values (e.g., total ash 5.53%, water-soluble extractive 17.41%): with aflatoxins absent and heavy metals (Pb, Cd, As, Hg) within WHO guidelines. This is quality-control research for authenticating the crude drug; it says nothing about therapeutic effect. (IJFANS karpasa root study)

What about the galactagogue studies?

An important boundary: the experimental galactagogue study of "Karpasa beeja" tested the cotton SEED (churna and 90% ethanol extract) in albino rats for 15 days, comparing it with shatavari: it did not test the root. (IJAM, 2020) Findings from the seed cannot be transferred to the root, and LactMed judges even the seed's galactagogue evidence inadequate. No efficacy trials of karpasa moola itself were found.

An experimental study from the University of Zambia found that crude root extracts of Gossypium hirsutum, a different cotton species, showed uterotonic potential on isolated uterine strips, with the aqueous extract most potent. This is a different species and an ex-vivo model; it offers context for the historical uterine use but is not evidence for G. herbaceum root in people. (IJRSI, 2023)

Safety & contraindications

FAQs

What is karpasa moola?

Karpasa moola is the root (root bark) of the cotton plant, Gossypium herbaceum. Ayurvedic sources describe the root bark as pungent and heating, pacifying Vata and Pitta. It is distinct from karpasa beeja (the seed), which has its own traditional uses and its own (also thin) research record. (Karpasa: Carak Samhita)

How is the root different from the seed?

Different parts, different evidence. The seed (karpasa beeja) was tested in one rat study for galactagogue activity; the root has essentially no efficacy research at all, but it does contain gossypol and carries the historical uterine-stimulant reputation. Never assume a finding about the seed applies to the root. (IJAM, 2020; LactMed, NCBI)

What is Karpasasthyadi taila?

Karpasasthyadi taila is a classical Ayurvedic medicated oil whose name indicates karpasa among its ingredients. It is a traditional formulation, and its clinical effects have not been established in modern trials. It should be used only under a qualified practitioner's guidance, given the cautions around the cotton plant's root.

Does karpasa moola increase breast milk?

There is no evidence it does. The galactagogue experiments tested cotton seed, not root, in rats, and the NIH's LactMed database concludes that clinical trials of Gossypium as a galactogogue are "small and inadequate to validate its efficacy." Galactagogue use should never replace evaluation of modifiable factors affecting milk production. (LactMed, NCBI)

Is karpasa moola safe in pregnancy?

No: avoid it. Cotton root bark was historically used as an emmenagogue and abortifacient precisely because of its uterine-stimulating action, and it contains gossypol. Anyone pregnant, planning pregnancy, or breastfeeding should not use karpasa moola without explicit qualified supervision. (Ellingwood, 1902)

Why is there so little research on the root?

The cotton plant is cultivated for fibre and seed oil, so pharmacological attention has gone to the seed (gossypol, galactagogue studies) and to quality standardization of the root as a crude drug. The root's traditional niche, uterine and vata-pacifying uses, has not been tested in controlled trials. (IJFANS karpasa root study)

Sources

Tier 1 — classical database, peer-reviewed journals

Tier 2 — government/tertiary medical databases

Tier 3 — historical materia medica

This article is for educational purposes only and is not medical advice. Consult a qualified practitioner before using any Ayurvedic preparation, especially if you are pregnant, nursing, or taking prescription medicines.