Educational information, not medical advice — ask your doctor or midwife.
Wood cranesbill is a wild meadow flower of northern Europe, used in Nordic folk medicine as a drying, tightening remedy for loose bowels and sore mouths. Its botanical name is Geranium sylvaticum. Norwegians call it skogstorkenebb; Finns call it metsäkurjenpolvi.
It grows in damp meadows, open woods and road verges, with violet-blue flowers in early summer. The root and the leafy parts were the pieces used. Both are rich in tannins, plant compounds with a dry, puckering taste.
Here is the honest verdict. No human trials of this plant have been published, so nothing about its effect in people is settled. Long traditional use is not proof that it works, and it is not proof that it is safe.
Nobody has shown what wood cranesbill does inside the human body. The ideas below come from chemistry and laboratory work, not from people.
The plant is high in tannins. In test tubes, tannins bind to proteins and make wet tissue surfaces feel tighter and drier. That is the classic astringent effect, and it is the reason folk use focused on diarrhoea, mouth rinses and weeping skin.
Lab tests on Geranium tannins also report antioxidant activity. Some slow the growth of bacteria in a dish. Whether any of that happens in a person's gut, mouth or skin has not been established.
Tannins are poorly absorbed from the gut. So most of any action would stay inside the gut rather than reach the blood. That is a reasonable chemical guess, not a measured fact.
Wood cranesbill is rarely sold. Most use has been home-made from wild-picked plants.
Dry forms you may meet:
- Dried root, cut or powdered. - Dried leaf and stem for tea.
Prepared forms you may meet:
- A water infusion or decoction, drunk or used as a gargle or skin wash. - A tincture, meaning an alcohol extract, from small herbal makers. - A minor ingredient in mixed Nordic herbal blends.
There is no standard extract and no agreed strength. Wild material can be misidentified. Roadside plants can carry traffic grime or spray residue.
Scandinavian folk healers treated wood cranesbill as an astringent, a remedy that dries and tightens. Records come mainly from folklore collections of the 1700s to the early 1900s, not from medical files.
Reported uses included drinks for diarrhoea, gargles for sore mouths and throats, and washes for grazes and weeping skin. Some accounts mention it for heavy periods. Cattle healers used similar tannin plants for scouring livestock.
The petals were also used locally as a blue-violet dye. Across the Atlantic, a cousin plant, American cranesbill (Geranium maculatum), was listed in old US pharmacy books for the same astringent purpose.
These are claims that people made, written down by collectors. They tell you what was believed, not what was tested.
Stop using it and see a doctor if any of these happen:
- Diarrhoea lasts more than two days, or returns straight after stopping. - You see blood or black, tarry stools. - You have fever, severe belly pain, or you cannot keep fluids down. - You feel dizzy, very weak, or your mouth stays dry and you pass little urine. These point to dehydration, meaning too little fluid in the body. - You get a rash, swelling of the lips or face, or trouble breathing. Get emergency help for these. - You are more tired, pale or breathless than usual, which can signal low iron.
Always tell your doctor or pharmacist about any herb you are taking. It changes how they read your symptoms.
Wood cranesbill is not a licensed medicine in any country we are aware of. It has no European Medicines Agency herbal monograph, and no approved medical claim in Norway, Sweden, Finland, the UK or the US.
It is treated as an ordinary wild plant. In the US it is not a common dietary supplement, and the FDA has not assessed it. Local rules on picking wild plants, including protected sites and nature reserves, still apply.
Evidence grades and traditional-use labels are explained in our methodology. Nothing here is medical advice.
Reviewed by the HealisticMD editorial team How we grade evidence →
The published evidence for Wood cranesbill is weak or absent. That usually means no controlled trial has tested it, not that a trial found it ineffective — the two are different, and we grade only what has been published.
What it is typically used for, usual dose, cautions, and the study behind it where real trial data exists.
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