Karveer (Nerium indicum Mill.): A Comprehensive Review of its Botanical, Phytochemical, Pharmacological, and Toxicological Profile

Abstract

In Ayurvedic texts more than 500 medicinal plants have been mentioned with their therapeutical uses; Karv?ra i.e. Nerium indicum is one of them.1,2 It is a very useful plant with various medicinal properties such as antimicrobial, anti-pruritus, wound healer, antileprotic, cardiac tonic, etc. Since long, it is being used by physicians in various diseases especially the skin diseases. Scientific studies now also support its use in a variety of conditions such as wound infections, inflammation, cancer, diabetes and CNS depression.3 All parts of the plant — root, bark, leaves, flowers and seeds — contain potent cardiac glycosides, primarily oleandrin, neriodorin, neriodorein, and nerifolin, which underlie both its therapeutic potential and its considerable toxicity.4 Karveer is classified as an Upavisha (sub-toxic plant) in Ayurveda and figures prominently in classical texts including Charaka Samhita and Sushruta Samhita for the management of skin disorders, fevers, cardiac insufficiency, and various inflammatory conditions.1 Scientific validation of its antimicrobial, anti-inflammatory, antifungal, and cardiotonic properties has grown steadily.5,6 However, the margin between therapeutic and lethal dose remains narrow, necessitating expert supervision and proper Shodhana (detoxification) before use.7 This review aims to serve as a reference for researchers, clinicians and students of Ayurveda and pharmacognosy.

Introduction

The text describes Karveer (Nerium indicum / oleander) as an important yet highly toxic medicinal plant widely recognized in Indian traditional medicine. India has a long history of using medicinal plants, and Karveer holds a unique position due to its dual nature—therapeutically valuable but potentially poisonous.

Botanically, it is an evergreen shrub from the Apocynaceae family, found across India and other Asian regions. It exists in different varieties based on flower color and contains milky latex, with roots and leaves commonly used for medicinal purposes despite their toxicity.

From an Ayurvedic perspective, Karveer has pungent and bitter properties, is heating in nature, and is used in very small, purified doses. It balances certain body elements (doshas) but can be harmful if misused.

Chemically, the plant contains powerful compounds, especially cardiac glycosides like oleandrin, which affect heart function similarly to digitalis. It also includes flavonoids, alkaloids, and other bioactive substances.

Pharmacologically, Karveer shows multiple effects, including cardiovascular stimulation, antimicrobial, anti-inflammatory, antipyretic, antioxidant, and potential anticancer activities. However, due to its high toxicity—especially affecting the heart—its use requires extreme caution and proper processing.

Overall, Karveer is a potent medicinal plant with significant therapeutic potential but a narrow safety margin, making careful handling and dosage essential.

Conclusion

Karveer (Nerium indicum Mill.) is a botanically, pharmacologically, and toxicologically significant plant with deep roots in Indian traditional medicine. Its therapeutic use in skin disorders, fevers, cardiac conditions, and inflammatory diseases is substantiated by both classical Ayurvedic documentation and modern scientific research.1,2,3 Simultaneously, its potent cardiac glycosides render it one of the most dangerous plants in the Indian pharmacopoeia when misused.4,7,15 Safe and effective use demands adherence to Shodhana protocols, precise dosing, professional supervision, and respect for contraindications. Further standardised clinical studies are warranted to define the therapeutic window more precisely and to explore the anticancer potential of its bioactive constituents under controlled conditions.13,14

References

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Copyright

Copyright © 2026 Dr. Shaloni Sharma, Dr. Sanjay Srivastava, Dr. Tanishka Gupta, Dr. Maninder Singh Sisodiya. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.