Senna: Benefits, Uses & Dosage

Most people meet Senna on a pharmacy shelf, as the active ingredient in an overnight laxative. Ayurveda knew it long before that, and treats it with real respect: it is a strong purgative (Virechana), an herb that empties the bowel decisively, and it is meant to be taken with care and in proper dosage.

Senna is Cassia angustifolia, known in Sanskrit as Markandika and Rajavriksha, and in Indian medicine also as Svarnapatri and Sanay. The leaves and pods are the medicinal parts. The Bhavaprakash Nighantu also mentions related species, Alexandrian senna (Cassia acutifolia) and Italian senna (Cassia obovata).

The plant thrives in dry, hot conditions and is described as especially good at purging dampness and heat. It is bitter and pungent in taste, cooling in potency, and dry, light, and penetrating in quality. It calms Pitta and Kapha but aggravates Vata, which shapes both where it helps and where it does harm.

Nearly every use of senna flows from one action: purgation. It works on the plasma, blood, and fat tissues through the digestive, excretory, and circulatory channels. The Bhavaprakash Nighantu lists its actions (Karma) as purgative (Virechana), laxative (Rechana), anthelmintic (Krimighna), and regulating the downward flow of Vata (Vatanulomana).

Severe constipation

Senna is mainly used for severe constipation, including constipation that follows a fever. The Bhavaprakash Nighantu describes it as an important purgative that produces reliable purgation, and senna is also listed in the British Pharmacopoeia.

Its downward-moving action (Vatanulomana) restores the natural flow of Vata toward elimination, which is why it is also linked with gas and flatulence.

Purgation therapy for Pitta

Senna is used for clearing Pitta from the small intestine, as in purgation therapy (Virechana), one of the classical cleansing procedures. Its cooling potency and bitter taste suit this heat-clearing role. It is also linked with liver disorders (Yakrit Roga).

Skin conditions

Senna is indicated for inflammatory skin conditions (Kushtha), and it is listed as an alterative, a blood-cleansing herb. Herbal practice combines it with gotu kola, manjishtha, neem, and bakuchi for skin problems that come with constipation.

Worms and parasites

As an anthelmintic (Krimighna), senna is associated with parasites and worms (Krimi). The purge clears the bowel while the herb acts against the worms themselves.

Weight and blood pressure

Herbal sources also list obesity and hypertension among senna's indications. Its dry, light, penetrating qualities oppose the heavy, oily qualities that build fat, but it is a tool for short, guided courses, never a daily slimming tea.

In classical formulas

The Sharangadhara Samhita (Parishishtam) includes senna (Svarnapatri) with trivrit, licorice, bala, turmeric, dry ginger, Triphala, and kutki in a compound formula for brain tremor, where senna and trivrit serve as the mild purgatives.

Senna is prepared as a hot or cold infusion of the leaves, as a powder, or as a tincture. The dose decides whether it acts as a laxative or a full purgative, so the numbers matter more here than with most herbs.

Always add a stomachic

Senna irritates the intestinal lining and can cause griping, the cramping pain of a forced bowel movement. Ayurvedic tradition corrects this by adding about one-quarter as much Ginger or fennel seed to each dose, or by making them 25 to 50% of the mixture.

Useful combinations

• Ginger or fennel: to prevent griping.
• Kushtha and mustaka: to help clear the intestines.
• Gotu kola, manjishtha, neem, and bakuchi: for skin problems that come with constipation.

Keep the course short

Laxatives containing anthraquinone glycosides, senna's active compounds, should not be used at a high dose for more than 2 weeks at a time. For gentle daily bowel support, Ayurveda turns to milder herbs instead.

Senna is a strong purgative, not a gentle tonic. Its classical description is explicit: it should be taken with care and in proper dosage. Here is what the sources say.

Do not use senna if you have

• Pregnancy, or are breastfeeding
• Inflammatory bowel disease or any inflammatory condition of the digestive tract
• Intestinal obstruction
• Hemorrhoids
• Diarrhea

Common side effects

Senna has an irritant effect on the intestinal membrane. It may cause griping, pain, or nausea, along with liquid stools or diarrhea. Adding ginger or fennel to each dose is the traditional correction.

Because it aggravates Vata, it can leave people who are already dry, anxious, or depleted feeling worse.

Electrolytes and the two-week limit

High doses should not be used for more than 2 weeks at a time. If senna causes diarrhea, the body can lose electrolytes, the salts that keep the heart and muscles working properly.

Drug interactions

Take particular care with heart medication of the cardiac glycoside type and with thiazide diuretics, since further electrolyte imbalance can cause problems. The same applies if long-term laxative overuse has already disturbed your electrolytes. Senna may also reduce the absorption of iron.

When to see a doctor

Severe abdominal pain, sudden changes in bowel habit, or constipation that keeps returning need a medical diagnosis before any purgative. Talk to your doctor before using senna if you take any prescription medication.

Senna is usually weighed against other bowel-clearing herbs. The key difference is strength: senna is a strong, drying purgative, while the alternatives below are gentler or work differently.

Comparison	Senna	Alternative	Verdict
Senna vs Triphala	Strong purgative for short courses; aggravates Vata	The gentle daily bowel tonic of Ayurvedic practice	Triphala for ongoing support; senna only for occasional severe constipation
Senna vs Castor oil	Dry, cooling, irritating; suits heat and dampness	A purgative that oils the bowel while it clears	Castor oil suits dry, Vata-type blockage; senna suits Pitta and Kapha patterns
Senna vs Haritaki	Short courses, limited to 2 weeks at higher doses	A gentler herb used for sustained constipation care	Haritaki for the long term; senna for a short, decisive clear-out
Senna vs Psyllium	Stimulates the bowel to move	Adds bulk fibre to soften stool	Psyllium for daily regularity; senna when a stronger push is needed

Senna is a strong purgative, so the question for most groups is not how much to take but whether to take it at all.

Pregnancy & Nursing

Avoid senna. Pregnancy and lactation are both listed contraindications, and classical precautions name pregnancy specifically. Talk to your doctor or midwife about safer options for constipation during this time.

Children

Our sources give no dosing for children, and senna's strength makes it a poor fit for a child's bowel. Do not give it to children without a pediatrician's advice.

Elderly

Vata tends to rise with age, and senna aggravates Vata. Older adults are also more likely to take heart medication or thiazide diuretics, where senna's effect on electrolytes needs particular care, so use it only with medical guidance.

Athletes

Senna has no performance role. Diarrhea from senna can disturb electrolyte balance, which matters for anyone training hard or sweating heavily, so avoid it around training and competition.