Educational information, not medical advice — ask your doctor or midwife.
Sahel senna is a small shrub of the dry West African Sahel. Its dried leaves and pods are used as a laxative, meaning a remedy that makes the bowels move. In Hausa it is called filasko.
The plant is Senna italica. It is a close relative of the senna sold in pharmacies for constipation. The leaves hold compounds called sennosides, and these are what stir the bowel.
In markets across the Sahel the dried leaf is sold loose, by the handful. Healers and families have used it for blocked bowels and for "cleansing". The same leaf is also used as animal feed and, in some places, as a wash for skin problems.
Here is the honest evidence picture. Senna as a drug class is well proven for short-term constipation, and that is not in doubt. But almost all of that testing used the pharmacy species, Senna alexandrina, in measured doses.
Senna italica itself has very little human testing. Its chemistry is close, so it very likely acts the same way. How strongly it acts in any given batch of market leaf is not known.
Long and respected traditional use is not proof that a remedy works, and it is not proof that it is safe. That applies here as it does to any herb. Read the rest of this page with that in mind.
One more thing worth saying early. Senna is a stimulant laxative, not a gentle food. It is meant for short use, and it can cause real harm when taken day after day.
Sennosides make the large bowel squeeze harder and hold more water, so stool moves and softens. This effect is well established in people for senna laxatives.
The sennosides do almost nothing by themselves. Gut bacteria break them down into a compound called rhein anthrone. That compound acts on the lining of the colon.
Two things then happen. The muscle of the bowel wall contracts more often. Less water and salt are pulled back out of the stool.
That is why senna takes hours, not minutes. The material has to reach the lower gut first.
For Senna italica the mechanism is assumed rather than measured. It carries the same family of compounds, so the same pathway is expected. Direct human studies of this species are lacking.
Laboratory work on Senna italica extracts has also reported effects on bacteria and on inflammation. Those were test-tube and animal studies. Whether any of that matters in a person is not established.
The repeated-use problem is also partly understood. Heavy ongoing use can flush out potassium, a salt your muscles and heart need. Low potassium can then make the bowel lazier, which tempts people to take more.
Most often it is the dried leaf, sold loose and brewed as a tea or steeped in cold water.
Other forms you may meet:
Dried pods, used the same way as the leaf.
Coarse leaf powder, stirred into water or a drink.
Powder packed into capsules by small producers.
Whole fresh plant used as fodder, which is not a medicinal use.
Pharmacy senna is a different product. It is usually Senna alexandrina, made into tablets or syrup. The sennoside content is measured and printed on the box.
That difference matters. With a labelled tablet you know roughly what you took. With market leaf you do not.
Senna italica has long standing across the Sahel and West Africa. Hausa speakers know it as filasko.
It was used mainly as a purge, to clear the bowels. Healers gave it for constipation and for a heavy, blocked feeling in the belly. It also appeared in seasonal "cleansing" practices.
Other recorded uses were wider. Leaf washes and pastes were applied to skin sores and ringworm. Preparations were sometimes given for fever or belly pain.
Senna has a long written record elsewhere too. Arab physicians wrote about senna leaf from around the 9th century. It entered European medicine from that route.
These records tell you the plant was trusted and widely used. They do not tell you what it treats safely today, and none of this history should be read as advice to dose yourself.
Stop and see a doctor if nothing has moved after a few days of use. Ongoing constipation needs a cause found.
Get medical help the same day if you have:
Severe or worsening belly pain.
Vomiting along with no bowel movement.
Blood in the stool, or black tarry stools.
Heavy watery diarrhoea that will not stop.
Go to an emergency department if you have muscle weakness, a racing or uneven heartbeat, fainting, or confusion. These can be signs of low blood salts.
In the UK, the EU and the US, senna laxatives are sold over the counter, but those products use Senna alexandrina and state their sennoside content. Senna italica leaf is not a licensed medicine in those places; it is traded as a herbal raw material and is common in West African markets.
Evidence grades and traditional-use labels are explained in our methodology. Nothing here is medical advice.
What it is typically used for, usual dose, cautions, and the study behind it where real trial data exists.
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