Pelargonium (Pelargonium sidoides)

Table of Contents

1. The Plant and Its Names
2. Traditional Use in Southern Africa
3. From "Consumption Cure" to Modern Extract
4. What Is in the Root
5. One Extract, One Research Programme
6. Acute Bronchitis: What the Trials Found
7. Colds, Sinusitis and Sore Throats
8. What Reviewers and Regulators Concluded
9. Laboratory Research: Antiviral and Immune Effects
10. Doses Used in Trials and Listed in the Monograph
11. Safety: Side Effects, Liver Reports and Interactions
12. The Deep-Dive Articles
13. Where the Evidence Stands
14. Key Research Papers
15. Connections
16. Featured Videos

The Plant and Its Names

Pelargonium sidoides belongs to the Geraniaceae, the same family as the pelargoniums sold as "geraniums" for window boxes. A conservation fact sheet describes its leaves as slightly aromatic, velvety and heart-shaped, and its flowers as dark reddish-purple. The part used in medicine is underground: thick, tuberous roots. A 2015 conservation fact sheet from the wildlife-trade monitoring network TRAFFIC describes the species as endemic to South Africa and Lesotho.

A close relative, Pelargonium reniforme, has similar roots and was historically mixed up with it. The European Pharmacopoeia defines "Pelargonium root" (Pelargonii radix) as the dried underground organs of either species, and the European Union herbal monograph covers both. Nearly all modern clinical research, however, used extracts of P. sidoides alone.

The common names reflect the plant's history: Umckaloabo (the trade name that grew out of the old remedy, and the name the Cochrane review uses as an alias), South African geranium, kalwerbossie (its Afrikaans name), and, in older English literature, Stevens' Cure.

Traditional Use in Southern Africa

Several tuberous Pelargonium species are important traditional medicines in southern Africa. A 2008 review of the plant's ethnobotany describes their stems or tubers being used for a variety of ailments, including the complications of dysentery, and calls this an under-estimated part of the region's traditional medicine. A pharmacology review by Kolodziej makes a point that surprises many readers: root extracts were most commonly used for dysentery and diarrhoea, and only occasionally for respiratory complaints.

The European Medicines Agency's 2024 assessment report summarises the traditional uses as infusions of the roots for coughs, chest problems including tuberculosis, and digestive disorders such as diarrhoea and dysentery, with the leaves used on wounds. The TRAFFIC fact sheet similarly lists relief for colic, diarrhoea and dysentery. The respiratory use that dominates the plant's modern reputation is therefore partly a European emphasis built on top of a broader African tradition.

From "Consumption Cure" to Modern Extract

According to the EMA assessment report, an Englishman named Charles Henry Stevens travelled to South Africa in 1897 on his doctor's advice, hoping the mountain air would cure his tuberculosis. There he was treated by a local traditional healer with a boiled root preparation; three months later he felt well and considered himself cured. Back in Britain he set up a company to sell the remedy as "Stevens' Consumption Cure" ("consumption" being the old name for tuberculosis).

In 1920 the French-Swiss physician A. Sechehaye began treating tuberculosis patients with Stevens' Cure in Geneva and reported on some 800 patients over nine years; a German physician described five successful cases in 1933. These were uncontrolled case reports from the era before antibiotics, with no comparison group. The tuberculosis claim was never confirmed by a controlled trial. Laboratory work summarised by the EMA found only modest activity of root extracts against the tuberculosis bacterium, and none for the isolated compounds tested; modern tuberculosis is treated with combinations of antibiotics, and no regulator lists tuberculosis as a use for pelargonium.

For decades nobody knew exactly which plant was in the remedy. In 1977 researchers at the University of Munich used botanical and chemical comparisons to show that the roots came from P. sidoides and/or P. reniforme. Marketing for bronchitis and cold symptoms began in the 1970s, the European Pharmacopoeia added a monograph for the root in 2008, and a standardised extract became the basis of the modern trials. The full story is in the deep-dive article Umckaloabo History and Wild Harvest.

What Is in the Root

Pelargonium root is chemically complex. Reviews of its chemistry describe:

• Simple coumarins. A notable range of highly oxygenated coumarins, including scopoletin and umckalin, a methoxylated coumarin that one review calls the plant's main characteristic constituent. Coumarin sulphates and glycosides appear to be confined to P. sidoides, which helps chemists tell the two species apart.
• Proanthocyanidins (condensed tannins). Oligomeric and polymeric chains of catechin and gallocatechin units, here called prodelphinidins. The EMA notes that these occur in high concentration, while most other compounds are present in small amounts. The Pharmacopoeia sets a minimum tannin content of 2 per cent.
• Gallic acid and its methyl ester, flavonoids, phenolic acids and a phytosterol.

The aerial parts (leaves and stems) have a different profile, rich in flavonoids and hydrolysable tannins, with fewer coumarins. The extract used in trials is made from roots with an ethanol-water mixture; a chemical comparison found its constituent profile matched that of P. sidoides root.

The word "coumarin" causes understandable worry because the blood thinner warfarin is a coumarin derivative. The coumarins identified in pelargonium root are a different structural type; this is covered under Safety below.

One Extract, One Research Programme

To read the pelargonium evidence correctly, three facts matter more than any single result:

1. Almost all trials tested one product. The randomised trials used a single standardised root extract coded EPs 7630, given as drops (an ethanol-water liquid) or as tablets. Results for that extract cannot automatically be transferred to teas, home tinctures or other commercial extracts.
2. Almost all trials came from one source. The EMA's 2024 assessment report states that the studies reviewed by the meta-analyses "were performed by all the same investigators (the manufacturer) and in the same region (Ukraine and Russia)". In other words, the evidence base is largely manufacturer-run research. That does not make the results false, but independent replication is scarce.
3. The main outcome was a symptom score. Most bronchitis trials measured the Bronchitis Severity Score (BSS), a 0–20 point score covering cough, sputum, chest sounds, chest pain on coughing and breathlessness. The EMA accepted the score as valid in 2013 but judged that the trials had not defined in advance what size of difference would matter to patients.

The Cochrane reviewers also flagged a suspicion of publication bias based on a funnel plot, meaning small negative studies may be missing from the published record.

Acute Bronchitis: What the Trials Found

Acute bronchitis is an infection of the airways in the chest, predominantly caused by viruses, whose main symptom is cough. It is the condition where pelargonium has the most trials.

Adults

In a 468-patient placebo-controlled trial published in 2003, the symptom score fell by 5.9 points with the liquid extract and 3.2 points with placebo after seven days, and inability to work fell to 16 per cent versus 43 per cent. A 124-patient trial found falls of 7.2 versus 4.9 points, and a 217-patient trial found 7.6 versus 5.3 points. A 406-patient tablet trial compared three doses with placebo: the score fell by 2.7 points on placebo and by 4.3, 6.1 and 6.3 points on 30 mg, 60 mg and 90 mg a day; side effects were mild to moderate and became more frequent with higher doses.

Children and adolescents

Two placebo-controlled trials in children aged 1 to 18 (200 and 220 participants) reported greater falls in the symptom score with the extract (3.4 versus 1.2 points, and 4.4 versus 2.9 points), with similar tolerability in both groups.

A pragmatic trial that did not find a benefit

The most recent and most independent trial points the other way. PHYTOBRONCH, a 2026 open-label trial in 36 Swiss family practices and five walk-in clinics, randomised 332 adults to the extract or to usual care. It found no significant difference in the time to halve symptoms, and antibiotic use was lower (17.4 versus 25.2 per cent) but not significantly so. Adverse events, all mild, were more frequent with the extract (32.3 versus 21.5 per cent). The authors declared no competing interests.

Every trial, the meta-analyses that pooled them, and the regulators' reasons for not accepting them as proof are covered in Acute Bronchitis Trials.

Colds, Sinusitis and Sore Throats

The evidence for other respiratory infections is thinner. The Cochrane review found one study in the common cold that showed a benefit after ten days but not after five, and one study of 103 adults with sinusitis that showed a significant effect on complete resolution at day 21; it rated both as very low quality evidence. A 2023 network meta-analysis of 47 trials of herbal medicines for rhinosinusitis ranked pelargonium among the most effective options for the common cold and for acute post-viral rhinosinusitis, with moderate certainty.

For sore throat and tonsillitis in children, a 2023 systematic review found only a handful of studies of any complementary therapy and judged their quality and quantity insufficient for a reliable conclusion. Details are in Sinusitis, Sore Throat and Colds.

What Reviewers and Regulators Concluded

• Cochrane review (2013 update). Of ten eligible studies, eight were analysed. For acute bronchitis in adults (three trials, 746 patients) and children (three trials, 819 children), the liquid preparation was effective for most outcomes but tablets were not; overall evidence quality was rated low. The reviewers concluded that pelargonium "may be effective" in relieving symptoms of acute bronchitis in adults and children, and that it may help acute sinusitis and the common cold in adults, "but doubt exists". Adverse events were more common with the extract, but none were serious.
• 2008 meta-analysis of acute bronchitis. Six trials met the criteria; pooling four placebo-controlled trials suggested the extract reduced symptom scores by day 7. The authors called the evidence "encouraging".
• 2015 meta-analysis of herbal medicines for cough. Across 34 trials of several herbs, it rated the evidence for pelargonium as moderate, behind andrographis and an ivy/primrose/thyme combination, which it rated as strong.
• 2018 meta-analysis in children. Six placebo-controlled trials gave moderate evidence for efficacy and safety in children's respiratory infections.
• European Medicines Agency (monograph revised 2024). The Committee on Herbal Medicinal Products concluded that the placebo-controlled trials were not adequate to prove efficacy, because no clinically relevant difference was defined in advance and none of the trials reached the size of effect the committee considered strongly relevant for a self-limiting illness. Pelargonium root is registered only as a traditional herbal medicinal product for the symptomatic treatment of the common cold, based on more than 30 years of use.

Laboratory Research: Antiviral and Immune Effects

Laboratory studies offer several possible explanations for how the extract could work, but they are cell-culture results, not proof of effect in people.

• Little direct killing of bacteria. Reviews describe only moderate direct antibacterial activity. Instead, in laboratory tests the extract appears to interfere with bacteria binding to host cells.
• Antiviral activity in cell culture. The extract inhibited replication of several respiratory viruses and the viral enzymes haemagglutinin and neuraminidase in laboratory tests. In a 2021 study of human lung cells, funded by the manufacturer and co-authored by its staff, it inhibited entry of the COVID-19 virus, SARS-CoV-2, with low-oligomer prodelphinidins among the most active fractions.
• Immune signalling. In cell experiments the extract changes the release of cytokines (the immune system's chemical messengers) and may stimulate monocytes while damping neutrophil-attracting signals. A 2025 review of this work in sinusitis noted that the number of studies is small and the level of evidence low.
• Cilia. An increase in the beating frequency of the tiny hairs that move mucus out of the airways has been reported in cell studies.

A 2023 mechanistic review concluded that pelargonium's possible routes of action are antiviral, indirectly antibacterial, immune-modulating and expectorant. None of these mechanisms has been confirmed in patients.

Doses Used in Trials and Listed in the Monograph

The adult bronchitis trials of the liquid extract gave 30 drops three times a day for seven days. The tablet trial tested 10, 20 and 30 mg three times a day; its authors concluded that 20 mg three times a day gave the best balance of benefit and side effects. The children's trials used 10, 20 or 30 drops three times a day depending on age band (1–6, 6–12 and 12–18 years).

The EU monograph (Revision 2, adopted May 2024) lists, for the traditional common-cold use:

• Liquid extract (1 part root to 8–10 parts solvent, 11% ethanol): 1.4 ml three times daily for adolescents over 12 and adults; 0.9 ml three times daily for children 6–12; 0.4 ml three times daily for children 3–5.
• Dry extracts: 20 mg three times daily (60 mg a day) for adolescents and adults; 40 mg a day for children 6–12; 20 mg a day for children 3–5, in liquid forms only under age six.

The monograph states that oral use under age three is not recommended, and that a doctor or qualified practitioner is to be consulted if symptoms last longer than a week or worsen. These figures report what trials and the monograph state; decisions about any medicine belong with a clinician.

Safety: Side Effects, Liver Reports and Interactions

Side effects in trials

In the trials, side effects were mostly mild: stomach upset, nausea, diarrhoea, and occasionally, in a pooled safety analysis cited by the EMA, nosebleeds or bleeding gums. The Cochrane review found adverse events more common with the extract than with placebo, but none serious. The EU monograph lists hypersensitivity reactions (including anaphylaxis), rash, itching, hives and swelling, nosebleeds, gum bleeding, digestive complaints, and liver injury, all with unknown frequency.

Liver injury reports

By June 2012 the German medicines regulator (BfArM) had received 30 spontaneous reports of liver problems linked to pelargonium products, including one patient with hepatitis who underwent a liver transplant. It judged the link to be at least possible in most cases and required a liver warning in product information. Two 2012 re-analyses of 15 and 13 spontaneously reported cases, using structured liver-specific causality scales, could not confirm pelargonium as the cause in any of them, citing other medicines, other illnesses and poor data quality. The EMA reports that serious liver cases continued to be reported at a very low rate between 2013 and 2023, and the EU monograph carries the warning: "Hepatotoxicity and hepatitis cases were reported in association with the administration of the medicinal product." See Liver Injury Reports and Safety.

Coumarins and blood thinners

Because the root contains coumarins, an interaction with warfarin-type anticoagulants has been described as theoretically possible. The EMA notes that the coumarins found in the extract lack the chemical features needed for anticoagulant activity, that a rat study found no change in clotting or in warfarin levels, and that the monograph lists no known interactions. The question has not been tested in people taking warfarin.

Pregnancy and young children

The monograph states that safety in pregnancy and breastfeeding has not been established and that use in those situations is not recommended, and that oral use under age three is not recommended. Products made as alcohol-based drops contain ethanol.

The Deep-Dive Articles

Four longer articles look at each part of the evidence in detail. They are collected on the Pelargonium Benefits Deep Dive hub:

• Acute Bronchitis Trials — every adult and child trial, the pooled analyses, and the 2026 Swiss trial that found no benefit.
• Sinusitis, Sore Throat and Colds — the thinner evidence beyond bronchitis.
• Liver Injury Reports and Safety — what the regulators found and what is still unknown.
• Umckaloabo History and Wild Harvest — from Stevens' Cure to a conservation question.

Where the Evidence Stands

Pelargonium root has one of the larger trial records of any herbal remedy for respiratory infections. Manufacturer-run placebo-controlled trials of one extract consistently report modest improvements in bronchitis symptom scores over a week, and several independent meta-analyses rate the evidence as low to moderate quality. Against that, the trials came mainly from one research programme in one region, European regulators did not accept them as proof of efficacy, tablets performed worse than drops in the Cochrane analysis, and the largest independent pragmatic trial (Switzerland, 2026) found no significant effect on symptom duration.

Side effects in trials were mostly mild, but liver-injury reports exist, causality is disputed, and the EU product information carries a liver warning. The plant's history includes a tuberculosis cure claim that was never substantiated, and its wild populations have been under harvesting pressure. Acute bronchitis and colds usually resolve on their own; questions about a cough that is severe, persistent, or comes with breathlessness, chest pain or high fever are for a clinician.

Key Research Papers

1. Timmer A, Günther J, Motschall E, et al. Pelargonium sidoides extract for treating acute respiratory tract infections. The Cochrane database of systematic reviews. 2013;2013(10):CD006323. PubMed PMID: 24146345
2. Timmer A, Günther J, Rücker G, et al. Pelargonium sidoides extract for acute respiratory tract infections. The Cochrane database of systematic reviews. 2008;(3):CD006323. PubMed PMID: 18646148
3. Agbabiaka TB, Guo R, Ernst E. Pelargonium sidoides for acute bronchitis: a systematic review and meta-analysis. Phytomedicine : international journal of phytotherapy and phytopharmacology. 2008;15(5):378-85. PubMed PMID: 18222667
4. Wagner L, Cramer H, Klose P, et al. Herbal Medicine for Cough: a Systematic Review and Meta-Analysis. Forschende Komplementarmedizin (2006). 2015;22(6):359-68. PubMed PMID: 26840418
5. Anheyer D, Cramer H, Lauche R, et al. Herbal Medicine in Children With Respiratory Tract Infection: Systematic Review and Meta-Analysis. Academic pediatrics. 2018;18(1):8-19. PubMed PMID: 28610802
6. Hoang MP, Seresirikachorn K, Chitsuthipakorn W, et al. Herbal Medicines for Rhinosinusitis: A Systematic Review and Network Meta-analysis. Current allergy and asthma reports. 2023;23(2):93-109. PubMed PMID: 36609950
7. Matthys H, Eisebitt R, Seith B, et al. Efficacy and safety of an extract of Pelargonium sidoides (EPs 7630) in adults with acute bronchitis. A randomised, double-blind, placebo-controlled trial. Phytomedicine : international journal of phytotherapy and phytopharmacology. 2003;10 Suppl 4:7-17. PubMed PMID: 12807337
8. Chuchalin AG, Berman B, Lehmacher W. Treatment of acute bronchitis in adults with a pelargonium sidoides preparation (EPs 7630): a randomized, double-blind, placebo-controlled trial. Explore (New York, N.Y.). 2005;1(6):437-45. PubMed PMID: 16781588
9. Matthys H, Heger M. Treatment of acute bronchitis with a liquid herbal drug preparation from Pelargonium sidoides (EPs 7630): a randomised, double-blind, placebo-controlled, multicentre study. Current medical research and opinion. 2007;23(2):323-31. PubMed PMID: 17288687
10. Matthys H, Lizogub VG, Malek FA, et al. Efficacy and tolerability of EPs 7630 tablets in patients with acute bronchitis: a randomised, double-blind, placebo-controlled dose-finding study with a herbal drug preparation from Pelargonium sidoides. Current medical research and opinion. 2010;26(6):1413-22. PubMed PMID: 20387996
11. Kamin W, Maydannik V, Malek FA, et al. Efficacy and tolerability of EPs 7630 in children and adolescents with acute bronchitis - a randomized, double-blind, placebo-controlled multicenter trial with a herbal drug preparation from Pelargonium sidoides roots. International journal of clinical pharmacology and therapeutics. 2010;48(3):184-91. PubMed PMID: 20197012
12. Kamin W, Ilyenko LI, Malek FA, et al. Treatment of acute bronchitis with EPs 7630: randomized, controlled trial in children and adolescents. Pediatrics international : official journal of the Japan Pediatric Society. 2012;54(2):219-26. PubMed PMID: 22360575
13. Bourqui A, Corpataux O, Bonofiglio F, et al. Pelargonium sidoides extract (EPs® 7630) versus usual care for acute bronchitis in Swiss primary care (PHYTOBRONCH): a pragmatic, open-label, randomised controlled trial. NPJ primary care respiratory medicine. 2026;36(1). PubMed PMID: 42014704
14. Büttner R, Schwermer M, Ostermann T, et al. Complementary and alternative medicine in the (symptomatic) treatment of acute tonsillitis in children: A systematic review. Complementary therapies in medicine. 2023;73:102940. PubMed PMID: 36868289
15. Brendler T, van Wyk BE. A historical, scientific and commercial perspective on the medicinal use of Pelargonium sidoides (Geraniaceae). Journal of ethnopharmacology. 2008;119(3):420-33. PubMed PMID: 18725280
16. Kolodziej H. Fascinating metabolic pools of Pelargonium sidoides and Pelargonium reniforme, traditional and phytomedicinal sources of the herbal medicine Umckaloabo. Phytomedicine : international journal of phytotherapy and phytopharmacology. 2007;14 Suppl 6:9-17. PubMed PMID: 17188477
17. Kolodziej H. Antimicrobial, Antiviral and Immunomodulatory Activity Studies of Pelargonium sidoides (EPs(®) 7630) in the Context of Health Promotion. Pharmaceuticals (Basel, Switzerland). 2011;4(10):1295-1314. PubMed PMID: 27721327
18. Papies J, Emanuel J, Heinemann N, et al. Antiviral and Immunomodulatory Effects of Pelargonium sidoides DC. Root Extract EPs® 7630 in SARS-CoV-2-Infected Human Lung Cells. Frontiers in pharmacology. 2021;12:757666. PubMed PMID: 34759825
19. Veldman LBM, Belt-Van Zoen E, Baars EW. Mechanistic Evidence of Andrographis paniculata (Burm. f.) Wall. ex Nees, Pelargonium sidoides DC., Echinacea Species and a Combination of Hedera helix L., Primula veris L./Primula elatior L. and Thymus vulgaris L./Thymus zygis L. in the Treatment of Acute, Uncomplicated Respiratory Tract Infections: A Systematic Literature Review and Expert Interviews. Pharmaceuticals (Basel, Switzerland). 2023;16(9). PubMed PMID: 37765014
20. Perić A, Vezmar Kovačević S, Barać A, et al. Immunomodulatory Effects of Pelargonium sidoides Extract (EPs7630) in the Treatment of Acute Rhinosinusitis. Expert reviews in molecular medicine. 2025;27:e25. PubMed PMID: 40660733

PubMed Topic Searches

1. PubMed: Pelargonium sidoides
2. PubMed: EPs 7630
3. PubMed: Pelargonium sidoides and liver injury
4. PubMed: Pelargonium sidoides conservation and harvesting

Regulatory and Conservation Sources

1. European Medicines Agency, Committee on Herbal Medicinal Products. European Union herbal monograph on Pelargonium sidoides DC; Pelargonium reniforme Curt., radix. Final, Revision 2. EMA/HMPC/648100/2022, 2024. EMA monograph (PDF)
2. European Medicines Agency, Committee on Herbal Medicinal Products. Assessment report on Pelargonium sidoides DC; Pelargonium reniforme Curt., radix. Revision 2. EMA/HMPC/765656/2022, 2024. EMA assessment report (PDF)
3. European Medicines Agency. Pelargonii radix: herbal medicine overview. EMA: Pelargonii radix
4. TRAFFIC. Harvesting threats: sustainable management of Pelargonium sidoides in South Africa and Lesotho. Fact sheet, April 2015. TRAFFIC fact sheet (PDF)

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Connections

• All Herbs
• Respiratory and Lung Herbs — the category this herb belongs to
• Pelargonium Benefits Deep Dive — the four detailed articles
• Bronchitis — the condition with the most pelargonium trials
• Common Cold — the indication in the EU monograph
• Sinusitis — acute sinus infection
• Tonsillitis — sore throat and tonsil infection
• Tuberculosis — the disease behind the old "Consumption Cure" story
• Echinacea — another herb trialled for colds
• Andrographis — rated alongside pelargonium in the cough meta-analysis
• Thyme — part of the ivy/primrose/thyme combination in the same reviews
• Elecampane — a traditional European cough root
• Ivy Leaf — the other herbal cough extract assessed in the same reviews
• Cold and Flu Treatments — the wider evidence on cold remedies

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