Educational information, not medical advice — ask your doctor or midwife.
Senna is a shrubby plant native to Egypt, the Arabian Peninsula, and parts of South Asia, whose leaves and pods have been prized in Unani and Islamic medicine since at least the 9th century. It was widely traded along ancient spice routes and appears in the writings of Ibn Sina (Avicenna), who described it as one of the most dependable cleansing herbs available. Today it remains one of the most studied and widely used herbal laxatives in the world, recognized by both traditional practitioners and conventional medicine.
Senna's primary active compounds — sennosides — pass through the stomach and small intestine largely unchanged, then get converted by gut bacteria in the colon into active forms called rhein anthrones. These compounds stimulate the muscles in the colon wall to contract more strongly, speeding up bowel movement. They also reduce water absorption from the colon, softening stool and making it easier to pass.
Senna is available as dried leaves (brewed into tea), dried pods, standardized capsules or tablets (most consistent dosing), liquid extracts, and loose powder. Teas and infusions are the most traditional Unani preparation. Standardized capsules and tablets offer the most predictable dosing for modern use. Pods tend to produce a gentler effect than leaves.
Senna has been a cornerstone of Unani medicine for over a millennium. Ibn Sina's Canon of Medicine (11th century) detailed its use for constipation and internal cleansing. It was introduced to European medicine via Arabic physicians and became one of the first herbal medicines to undergo systematic pharmaceutical standardization in the modern era. It remains an FDA-approved over-the-counter laxative ingredient today.
Evidence grades and traditional-use labels are explained in our methodology. Nothing here is medical advice.
Everyday descriptions of the problems this remedy is recommended for.
Each grade below is for that condition specifically, not for Senna (Unani) in general.
The 19 options with the best evidence for Constipation, each with its grade and who should avoid it. One email.
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