# Tormentil (Potentilla erecta)

**Tormentilla*; septfoil, bloodroot*

**Known today as.** *Potentilla erecta*, of the rose family, a small yellow four-petalled flower of heaths, with a woody root red within.

Kind: Plant

## What was it used for?

One of the strongest astringents of the herbal: the root for fluxes, dysentery, and bleeding, and in gargles for the mouth and throat. Its name is from *tormina*, the griping of the bowels.

## What does modern science say?

The root is very rich in tannins; small studies have tried it against diarrhoea and ulcerative colitis.

## Pharmacognosy and toxicology

- **agrimoniin**: an ellagitannin
- **catechin tannins**: 15–20 per cent in all
- **tormentoside**: a triterpene glycoside
- **tormentillic acid**: 

**Mechanism.** The most tannin-rich root of the European flora: protein precipitation tightens the gut lining, stops bleeding, and kills microbes on contact, and a trial of tormentil extract in children with rotavirus diarrhoea shortened it from five days to three (Subbotina, 2003); another in ulcerative colitis lowered the disease index.

**Dose.** Safe at pharmacopoeial doses; large doses nauseate.

**Standing.** EMA monograph (2011) for mild diarrhoea and mouth inflammation, on tradition.

## What lore surrounds it?

In Orkney and the Western Isles the root was used to tan leather, and it gave a red dye.

## What did the older authorities say?

**Culpeper.** “A gallant herb of the Sun,” most excellent to stay all fluxes of blood; with Venice treacle and the patient laid to sweat it expels poison and the plague, “for it is an ingredient in all antidotes or counter poisons”; he cites Andreas Urlesius that its decoction cures the French pox as well as guaiacum or China root; the powder in plantain juice for those who cannot hold their water.

## Sources

- Grieve, M. (1931). *A Modern Herbal*, “Tormentil.”
- Gerard, J. (1597). *The Herball*.
- Culpeper, N. (1653). *The Complete Herbal*, “Tormentil, Or Septfoil.” Project Gutenberg #49513.
- EMA/HMPC (2011). *Community herbal monograph on Potentilla erecta (L.) Raeusch., rhizoma* (EMA/HMPC/527028/2010).
- Subbotina, M. D., et al. (2003). “Effect of oral administration of tormentil root extract on rotavirus diarrhea in children: a randomized, double blind, controlled trial.” *Pediatric Infectious Disease Journal* 22.

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*Tormentil.* In *Materia Medica*, edited by B. C. P. Statema. Version 1, revised 2026-10-01. The Thinking Press. https://thethinkingpress.org/materia-medica/tormentil

Historical description, not medical advice.