# Senna

> Senna (Cassia angustifolia Vahl (syn. Senna alexandrina Mill.)) is a plant used in Ayurveda, from the Fabaceae (Leguminosae/Caesalpiniaceae) family. Listed in WHO Monographs on Selected Medicinal Plants Vol.

## Key facts

- **Botanical name:** Cassia angustifolia Vahl (syn. Senna alexandrina Mill.)
- **Family:** Fabaceae (Leguminosae/Caesalpiniaceae)
- **Pharmacopoeia status:** Listed in WHO Monographs on Selected Medicinal Plants Vol. 1 (1999); European Medicines Agency well-established use monograph; included in multiple national pharmacopoeias worldwide

## Names and identification

| Language | Name |
|----------|------|
| English | Senna |
| Latin/Botanical | *Cassia angustifolia Vahl (syn. Senna alexandrina Mill.)* |

## Key Phytochemical Constituents

- Sennosides A and B ([rhein](/glossary/compounds-q-t/#rhein) dianthrone [glycosides](/glossary/compounds-g-l/#glycosides) - primary active)
- Sennosides C and D (rhein-aloe-[emodin](/glossary/compounds-d-g/#emodin) heterodianthrones)
- Rhein and rhein-anthrone (active metabolites)
- Aloe-emodin
- [Kaempferol](/reference/kaempferol/) and its glycosides
- [Isorhamnetin](/glossary/compounds-g-l/#isorhamnetin)
- [Chrysophanol](/glossary/compounds-c-d/#chrysophanol)
- [Mucilage](/glossary/compounds-l-o/#mucilage) and [polysaccharides](/glossary/compounds-o-q/#polysaccharides)

## How does it work?

- [Laxative](/reference/laxative/) mechanism: sennosides are hydrolyzed by colonic bacteria to release rhein-anthrone, which acts as a local irritant stimulating colonic peristalsis and inhibiting water/electrolyte absorption
- Anthraquinone-mediated [antimicrobial](/reference/antimicrobial/) action through disruption of bacterial membrane integrity and interference with DNA/RNA synthesis
- [Antioxidant](/reference/antioxidant/) mechanism through phenolic and flavonoid constituent scavenging of free radicals, reducing oxidative cellular damage

## Which traditional uses are supported by research?

- Laxative efficacy extensively validated through clinical studies and pharmacological research, confirming premier traditional use as a bowel stimulant (Virechana dravya)
- Antimicrobial properties validated against multiple bacterial and fungal strains, supporting broader traditional applications beyond purgation
- Anti-inflammatory properties partially validated through preclinical studies, though this is not the primary traditional indication

## What do recent clinical trials show?

- Alshehri MM, Quispe C, Herrera-Bravo J and others 2022. [A Review of Recent Studies on the Antioxidant and Anti-Infectious Properties of Senna Plants](https://pubmed.ncbi.nlm.nih.gov/35154569/). *Oxidative medicine and cellular longevity*. PMID [35154569](https://pubmed.ncbi.nlm.nih.gov/35154569/) · [doi:10.1155/2022/6025900](https://doi.org/10.1155/2022/6025900)  
  Documented significant antioxidant and anti-infectious properties of Senna species beyond traditional laxative use, with potential applications in antimicrobial therapy.

*2 further claims previously listed here could not be traced to a published paper and have been removed. An absence here means we could not identify the source, not that no work exists.*

## Recent safety updates

- EMA and WHO recommend use for no more than 1-2 weeks without medical supervision; chronic use may lead to electrolyte imbalance (hypokalemia), melanosis coli, and rarely hepatotoxicity (LiverTox likelihood score D - possible rare cause)
- Severe hepatotoxicity is unusual but documented in cases of chronic overuse; one case of acute liver failure with portal vein thrombosis reported; Cassia angustifolia extract was found not hepatotoxic at doses higher than normal in controlled in vitro/in vivo study

## What is it made of?

### Key Active Markers

- Rhein
- Glycosides
- Emodin
- Kaempferol
- Isorhamnetin
- Chrysophanol
- Mucilage
- Polysaccharides

**Analytical Methods:** HPLC fingerprinting, TLC (identity), LC-MS/MS (marker quantification)

## Dosage forms and preparation

**Dosage Forms:** Tablet, Capsule, Tea/Infusion, Syrup, Granules, Churna (powder), Standardized extract tablet

**Standard Dosage:** 15-30 mg sennosides (calculated as sennoside B) per day for adults; 0.5-2 g leaf powder; 1-2 g pod powder; use for maximum 7-10 consecutive days

**Bioavailability:** Sennosides are prodrugs — poorly absorbed intact in the small intestine (<5% systemic absorption). Colonic bacteria (Bifidobacterium, Bacteroides) convert sennosides to rhein-anthrone, the active metabolite, which acts locally on colonic mucosa to stimulate peristalsis and electrolyte secretion. Onset of action: 6-12 hours (overnight effect). This colonic-targeted mechanism is therapeutically advantageous.

**Optimal Timing:** Single dose at bedtime for morning bowel movement (6-12 hour onset); take with adequate water (250 mL minimum)

**Standardized Extract:** Standardized leaf extract per USP: NLT 6.0% total sennosides (as sennoside B) by HPLC. Pod extract: NLT 2.5% total sennosides. Typical commercial extract: 8-20% sennosides.

**Shelf Life:** 36 months for standardized extract tablets in blister packaging; 24 months for dried leaf/pod; 18 months for tea bags

**Storage:** Store below 25 deg C, protected from light and moisture. Sennosides are photolabile — amber or opaque packaging required. RH <60%.

**Marker Compounds:** Sennoside A, Sennoside B, Rhein, Aloe-emodin, Kaempferol, Isorhamnetin

### Extraction Methods

- Aqueous extraction (hot water infusion at 80-90 deg C, 10-15 min)
- Hydroalcoholic extraction (40-60% ethanol)
- Standardized extraction per USP/PhEur monograph
- Spray-drying of aqueous extract for powder form

### Synergistic Combinations

- [Haritaki](/herb/haritaki/) ([Triphala](/herb/triphala/)-based laxative formulations)
- [Fennel](/herb/fennel/)/Saunf (carminative addition to reduce griping)
- Psyllium husk (bulk-forming + stimulant laxative combination)
- [Ginger](/herb/ginger/) (reduces nausea and griping associated with senna)

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Canonical version of this page: https://nighantu.ageayurveda.com/herb/senna/

## Sources

- Amidha Ayurveda Herb Database (700+ herbs, CC-BY-4.0)
- Web research (clinical trials, WHO monographs, safety databases)
- Ayurvedic Pharmacopoeia of India

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.