Ayurvedic Properties
- Taste (Rasa)
- Bitter (Tikta), Astringent (Kashaya)
- Quality (Guna)
- Light (Laghu), Dry (Ruksha)
- Potency (Virya)
- Hot (Ushna)
- Post-digestive (Vipaka)
- Pungent (Katu)
- Key Constituents
- Bonducin (C20H28O8), Saponin, Oil, Phytosterol, Sitosterol, Heptocosane
- Also Known As
- English: Fever Nut, Physic Nut, Bonduc Nut
Sanskrit: करंज, कण्टकारंज, कुपटकरंज, विटपकरंज, कुबेराक्ष, पर्वतीय
Hindi: कँट करंज, कटकरंज, कण्टकरेज
What is Fever Nut?
Some fevers come and go in waves, returning every day or every few days. Ayurveda calls these intermittent fevers (Vishama Jvara), and its classic answer is a hard grey seed with an intensely bitter kernel: the Fever Nut.
Fever Nut (Kantakaranja), also called Bonduc Nut or Physic Nut, is Caesalpinia bonducella, with Caesalpinia crista named as a closely related source. It is a thorny climber with feathery, twice-divided leaves and yellow flowers, growing up to about 2,500 feet in many parts of India.
Its seeds are the main medicine. The Bhavaprakash Nighantu describes the kernel as extremely bitter and uses it to break the cycle of periodic fever, with a bark decoction as follow-up and the seed oil, known as Hongay oil, applied to the skin.
Benefits of Fever Nut
Fever Nut is bitter (Tikta) and astringent (Kashaya), light (Laghu) and dry (Ruksha), with a heating potency (Ushna Virya) and a pungent post-digestive effect (Katu Vipaka). The Bhavaprakash Nighantu lists five actions (Karma) for it.
Intermittent and periodic fevers
This is the herb's signature use. The seed kernel is an antipyretic (Jvaraghna) considered particularly effective against intermittent fevers, and the bark is also used in periodic fevers. The Sahasra Yoga drug index likewise notes the seeds for intermittent fevers.
Worms and parasites
Fever Nut is anthelmintic (Krimighna), used to help clear intestinal worms and parasites.
Inflammation
It is listed as anti-inflammatory (Shothahara), which links it to inflammation and swelling.
Digestion
Fever Nut kindles the digestive fire (Deepana). In Ayurveda, digestive fire (Agni) is the body's power to digest food and transform it into tissue. The text also credits it with removing abdominal masses (Gulma).
Skin, through the seed oil
The seed oil, Hongay oil, is used externally for skin diseases including scabies and herpes.
How to Use Fever Nut
Each part of the plant has its own use. The doses below are from the Bhavaprakash Nighantu and use traditional Indian weights: a ratti is a small seed-based weight, a fraction of a gram, and a tola is a larger unit.
| Form | Dose | Best For | When to Take |
|---|---|---|---|
| Seed kernel powder | 1 to 3 ratti | Intermittent fevers | Under practitioner guidance, to break the fever cycle |
| Bark decoction (Kashaya) | 2 to 4 tola | Periodic fevers | Follows the seed, as directed by a practitioner |
| Seed oil (Hongay oil) | Applied externally | Scabies, herpes and other skin complaints | On the skin only |
Our sources do not give a specific vehicle (Anupana) or seasonal guidance for Fever Nut. The very small seed dose is a reminder that this is a strong, bitter medicine, best used with professional supervision.
Safety & Side Effects
Our sources do not list specific contraindications or drug interactions for Fever Nut, so the guidance here is deliberately cautious.
- Tiny seed dose. The classical seed dose is only 1 to 3 ratti, a fraction of a gram. Do not exceed it.
- Heating and drying. With a hot potency and dry, light qualities, it may not suit people who already run hot or dry.
- Oil is external. Hongay oil is described for use on the skin, not for swallowing.
- Fever needs a diagnosis. Recurring fevers can signal serious infections. See a doctor before treating them yourself.
Recommended: Start Here
Fever Nut is a strong, bitter medicine, so the best way to start is with a qualified Ayurvedic practitioner who can confirm whether it suits you and set the dose. Recurring fevers also need a medical diagnosis first.
If you buy the powder, look for Caesalpinia bonducella or Caesalpinia crista on the label, and keep to the classical seed dose of 1 to 3 ratti. For skin complaints, the external seed oil is the traditional route.
Find Fever Nut Powder on Amazon ↗ Bonduc Nut Seeds ↗
Safety note: Use only tiny doses under guidance, keep the oil external, and avoid it in pregnancy and in children unless a practitioner prescribes it.
Fever Nut vs Other Herbs & Supplements
Fever Nut is a specialist herb. The most useful comparisons are between its own parts and between plants that share its names.
| Comparison | Fever Nut | Alternative | Verdict |
|---|---|---|---|
| Seed kernel vs bark | Seed kernel, 1 to 3 ratti, extremely bitter, used to break intermittent fever | Bark decoction, 2 to 4 tola, used in periodic fevers | The seed leads; the bark decoction follows. |
| Internal seed vs Hongay oil | Seed taken internally for fever, worms and digestion | Seed oil applied externally for scabies and herpes | Choose by the problem: internal complaints versus skin. |
| Fever Nut vs other plants called Karanja | Caesalpinia bonducella, also listed as Lata Karanja and Kantakaranja | Other plants share the name Karanja | Always confirm the botanical name on the label. |
Fever Nut for Specific Populations
Pregnancy & Nursing
Our sources give no safety data for pregnancy or nursing. Because Fever Nut is potent, heating and acts on abdominal masses, avoid it unless a qualified practitioner prescribes it.
Children
No child dosing is given in our sources. Fever in children needs medical assessment, so do not give Fever Nut without professional guidance.
Elderly
Older adults tend toward dryness, and Fever Nut is dry and heating. Use only under supervision, at the lowest dose.
Athletes
Fever Nut has no classical role in strength or performance. Its uses are fever, worms, inflammation, digestion and skin.
Frequently Asked Questions
Why is it called Fever Nut?
The extremely bitter seed kernel is used as an antipyretic, especially for intermittent fevers (Vishama Jvara) that come and go in cycles. The Sahasra Yoga drug index also records the seeds for intermittent fevers.
What is Hongay oil?
Hongay oil is the oil pressed from Fever Nut seeds. It is used externally for skin diseases including scabies and herpes.
What is the active compound in Fever Nut?
Chemical analysis identifies bonducin as the key active principle. The seeds also contain saponin, oil, phytosterols including sitosterol, and heptacosane.
What other names does Fever Nut have?
In English it is also called Bonduc Nut and Physic Nut. Sanskrit names include Kantakaranja, Kuberaksha, Lata Karanja and Dhanadanayana, and in Hindi it is known as Kat Karanj.
Does Fever Nut help digestion?
The Bhavaprakash Nighantu lists it as kindling the digestive fire (Deepana) and as removing abdominal masses (Gulma). Use it for this only with practitioner guidance, given its potency.
How to Use Fever Nut by Condition
Explore how Fever Nut is used for specific health concerns — with dosage, preparation methods, and classical references for each.
Medical Disclaimer: The information on this page is for educational purposes only and is not intended as medical advice. Ayurvedic treatments should be pursued under the guidance of a qualified practitioner (BAMS/MD Ayurveda). Always consult your healthcare provider before starting any new treatment. Content is sourced from classical Ayurvedic texts and may not reflect the latest medical research.