Sorrel Herb (Rumex acetosa): Benefits, Dosage, Safety & Evidence

Frequently asked questions

How does sorrel herb work medicinally?

Sorrel acts primarily through its high content of organic acids and tannins. The presence of oxalic acid provides a cooling, refrigerant effect, which traditionally helps reduce fevers and inflammation. Tannins contribute astringent properties, binding to mucous membranes to tone the digestive tract and alleviate minor diarrhea. Additionally, its significant vitamin C content supports immune function and collagen synthesis, historically explaining its use in treating scurvy (Evidence Level: Traditional/C).

Is sorrel safe to consume during pregnancy?

No, medicinal use of sorrel is considered unsafe during pregnancy. The herb contains significant amounts of oxalic acid, which can strain the kidneys and interfere with mineral absorption necessary for fetal development. Historically, sorrel was used to stimulate menstruation, posing a theoretical risk of miscarriage. Pregnant women should avoid concentrated medicinal doses, though small culinary amounts in soups are generally considered lower risk but should still be limited (Evidence Level: C/D).

What is the recommended dosage for sorrel herb?

For therapeutic use, the typical adult dosage of dried sorrel herb is 2 to 5 grams daily, usually prepared as a tea. Fresh young leaves can be eaten freely as a culinary vegetable, similar to spinach, though cooking helps reduce oxalic acid content. Due to the risk of kidney stones, long-term use of high doses is discouraged. It is best used as a seasonal spring tonic rather than a daily supplement (Evidence Level: Traditional/C).

Does sorrel interact with any medications?

Sorrel has potential interactions due to its high oxalic acid content. It may interfere with the absorption of calcium and other minerals, potentially reducing the effectiveness of antacids or mineral supplements. Because sorrel acts as a mild diuretic, it may alter the excretion rates of various drugs. Patients taking diuretics or medications metabolized by the kidneys should exercise caution and consult a healthcare provider (Evidence Level: C/Theoretical).

Can sorrel cause kidney stones?

Yes, sorrel is contraindicated for individuals with a history of kidney stones. The herb is rich in oxalic acid, which binds with calcium to form calcium oxalate, the primary component of most kidney stones. Excessive consumption can increase the risk of stone formation or exacerbate existing conditions. People with rheumatoid arthritis, gout, or hyperoxaluria should also avoid this herb due to the potential for aggravating joint inflammation (Evidence Level: C).

PubMed-compiled information sheet

This sheet was compiled from PubMed (NIH) abstracts using AI assistance. Every factual claim is cited to a real PubMed article (see the source list). It has not yet been human-reviewed — confirm with a healthcare provider before use.

Compiled from 30 PubMed articles · model: gemma4:31b

Summary

Rumex acetosa, also known as sheep's sorrel or red sorrel, is a flowering plant in the Polygonaceae family used as a vegetable and traditional medicine [PMID:33474359, PMID:40244509].

Background

Rumex acetosa is a species of flowering plant in the buckwheat family Polygonaceae [PMID:33474359]. It is a dioecious species characterized by a multiple sex-chromosome system [PMID:16498461, PMID:19085011].

Traditional uses

It is commonly used as a vegetable or a medicinal plant [PMID:30708739] and is known in traditional medicine for its therapeutic efficacy as an antihypertensive [PMID:29560776].

Active compounds

Major chemical constituents include anthraquinones (emodin, chrysophanol, and physcion) and their corresponding glucosides (emodin-8-O-β-d-glucoside, chrysophanol-8-O-β-d-glucoside, and physcion-8-O-β-d-glucoside) [PMID:38024697]. It also contains proanthocyanidins, total phenols, flavonoids, and flavanols [PMID:35161282]. Emodin is identified as a major component of the extract [PMID:32545588].

Mechanism of action

In the cardiovascular system, it exhibits vasorelaxant and antihypertensive effects [PMID:29560776]. It inhibits collagen-induced platelet aggregation and ATP release by suppressing intracellular calcium ion ([Ca2+]i) mobilization and integrin αIIbβ3 activation [PMID:32204703]. In the brain, it enhances cognitive function by activating cyclic AMP-responsive element-binding protein (CREB) via NMDA receptor 2 subunits (NR2A and NR2B), postsynaptic density protein-95 (PSD-95), and AMPA receptor subunit (GluA1) signaling [PMID:40244509]. It also inhibits the adhesion of Porphyromonas gingivalis to eukaryotic host cells [PMID:34953469].

Clinical evidence

Evidence DCognitive Function

Enhanced learning and memory in rats via modulation of NMDA receptor and BDNF pathways [PMID:40244509]

Evidence DHypertension

Crude methanol extract and aqueous fractions caused a significant fall in mean arterial pressure (MAP) in normotensive and hypertensive rats [PMID:29560776]

Evidence DPlatelet Aggregation

Markedly inhibited collagen-induced platelet aggregation and ATP release in a dose-dependent manner in rats [PMID:32204703]

Evidence DH. pylori Infection

Six isolated compounds (anthraquinones and glucosides) showed anti-H. pylori activity [PMID:38024697]

Evidence BPorphyromonas gingivalis (Oral Health)

A randomized placebo-controlled pilot trial evaluated a 0.8% proanthocyanidin-enriched extract mouth rinse on microbiological and clinical parameters [PMID:34953469]

Safety & adverse effects

A case report associated a large amount of sorrel intake with acute tubulointerstitial nephritis [PMID:25874577].

Drug interactions

Rumex acetosa extract may alter the pharmacokinetics of fexofenadine; emodin inhibits P-glycoprotein (P-gp) in vitro and in vivo, and the extract inhibits fexofenadine uptake via OATP1A2, resulting in a smaller area under the plasma concentration-time curve (AUC) [PMID:32545588].

Evidence summary

Evidence is primarily based on in vitro studies and animal models (Level D), with one small randomized controlled pilot study (Level B) regarding oral health. Human safety data is limited to a single case report.

PubMed sources

1.PMID: 33474359 (2018) — Characterization of the complete chloroplast genome of sorrel (Rumex acetosa). · Mitochondrial DNA. Part B, Resources
2.PMID: 39270415 (2024) — Root exudate-assisted phytoremediation of copper and lead contamination using Rumex acetosa L. and Rumex K-1. · Ecotoxicology and environmental safety
3.PMID: 32545588 (2020) — Effect of Rumex Acetosa Extract, a Herbal Drug, on the Absorption of Fexofenadine. · Pharmaceutics
4.PMID: 26025526 (2015) — The genomics of plant sex chromosomes. · Plant science : an international journal of experimental plant biology
5.PMID: 30708739 (2014) — First Report of Rhizoctonia solani AG-1-IB Causing Leaf Blight of Sorrel (Rumex acetosa) in Brazil. · Plant disease

Sorrel Herb

Sources & Citations

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