Tropaeolum Majus Herb (Tropaeolum majus): Benefits, Dosage, Safety & Evidence

Frequently asked questions

How does Tropaeolum majus work as a natural antibiotic?

Tropaeolum majus contains glucotropaeolin, a glucosinolate that converts to benzyl isothiocyanate when the plant tissue is damaged. This compound exhibits broad-spectrum antimicrobial activity by disrupting bacterial cell membranes and inhibiting enzyme function. The herb also contains vitamin C and quercetin, which provide antioxidant and immune-supporting effects. These mustard oil compounds are responsible for its traditional use against urinary and respiratory infections (Evidence Level C).

Can Tropaeolum majus be taken with prescription medications?

Tropaeolum majus may interact with medications processed by liver enzymes, as isothiocyanates can affect cytochrome P450 activity. The herb's antimicrobial properties could potentially interfere with antibiotic treatments. Most importantly, those taking thyroid medications should avoid this herb, as isothiocyanates may interfere with thyroid hormone production and medication efficacy. Always consult a healthcare provider before combining with prescription drugs.

What is the recommended dosage of Tropaeolum majus for medicinal use?

For adults, the standard dosage is up to 5 grams of fresh herb daily. The leaves and flowers can be consumed freely as food in salads or prepared as a medicinal infusion. Fresh plant material is preferred, as the active isothiocyanate compounds are most potent when the plant is freshly harvested. Start with smaller amounts to assess tolerance before increasing to the full recommended dose.

Is Tropaeolum majus safe to use during pregnancy?

Tropaeolum majus is considered unsafe during pregnancy and should be avoided. The isothiocyanate compounds may stimulate uterine contractions and could potentially harm fetal development. There is insufficient safety data for breastfeeding, so avoidance is recommended during lactation as well. Women who are pregnant, planning pregnancy, or breastfeeding should not use this herb medicinally. Culinary amounts may be less concerning, but consult a healthcare provider first.

Who should not take Tropaeolum majus?

Individuals with kidney disease should avoid Tropaeolum majus, as the isothiocyanates can irritate the urinary tract and potentially worsen renal function. Those with thyroid conditions should also avoid this herb, as compounds may interfere with thyroid hormone production. People with gastritis, stomach ulcers, or sensitive digestion should use caution, as high doses can cause gastrointestinal irritation. Discontinue use if stomach upset occurs.

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

Tropaeolum majus (garden nasturtium) is a medicinal plant native to South America containing bioactive compounds with antimicrobial, anti-inflammatory, and antioxidant properties [PMID:29766690, PMID:27161402].

Background

Tropaeolum majus L., belonging to the family Tropaeolaceae, is an edible flower plant used for ornamental, medicinal, and food purposes [PMID:29766690, PMID:35336212, PMID:35465202].

Traditional uses

It has been used as a disinfectant, an antibiotic, and for wound healing [PMID:28659749]. It is also traditionally consumed and used in popular medicine [PMID:36615228].

Active compounds

Key compounds include benzyl glucosinolate and its breakdown product benzyl isothiocyanate (BITC) [PMID:38792178, PMID:36816870, PMID:33862976]. Other bioactive constituents include anthocyanins, polyphenols, vitamin C, isoquercitrin, chlorogenic acid, and phylloxanthobilins [PMID:29766690, PMID:38843802, PMID:36293253]. It is also a source of micro elements (potassium, phosphorus, calcium, magnesium) and macro elements (zinc, copper, iron) [PMID:29766690].

Mechanism of action

The herb dually blocks the COX and LOX pathways in primary human immune cells [PMID:27161402]. Phylloxanthobilins exhibit anti-inflammatory effects via COX-1 and COX-2 enzyme inhibition [PMID:38843802]. In combination with low-dose gamma radiation, it suppresses liver carcinoma progression via the EGFR-HER2 signaling pathway and enhances proapoptotic markers (caspase-3 and Bax) while inhibiting the anti-apoptotic factor BCl2 [PMID:35834717].

Clinical evidence

Evidence BAcute Bronchitis

A combination of Tropaeolum majus herb and Armoracia rusticana root showed a statistically significant accelerated healing of bronchitis symptoms after three days compared to placebo [PMID:37167822]

Evidence CUncomplicated Urinary Tract Infections (UTI) and Respiratory Infections

Isothiocyanates from nasturtium have demonstrated positive results and good compatibility in the therapy of uncomplicated UTI and respiratory infections, and are recommended in the German S3 guideline for recurrent UTI prophylaxis [PMID:32789672]

Evidence BLipid Regulator Prostaglandin E2

In a crossover study of healthy females, nasturtium intervention containing BITC resulted in an increase in mean PGE2 levels in serum samples and ex vivo stimulated peripheral blood mononuclear cells [PMID:37599682]

Safety & adverse effects

A 90-day oral toxicity study in mice, rats, and rabbits using hydroethanolic extract of leaves showed no alterations in body weight gain, relative weight of liver, kidney, and spleen, or histopathological changes [PMID:29565700].

Evidence summary

Evidence ranges from high-level clinical trials for respiratory infections (B) to preclinical in vitro and in vivo studies (D) demonstrating anticancer, antimalarial, and anti-adipogenic activities.

PubMed sources

1.PMID: 29766690 (2018) — Garden nasturtium (Tropaeolum majus L.) - a source of mineral elements and bioactive compounds. · Roczniki Panstwowego Zakladu Higieny
2.PMID: 27161402 (2016) — Nasturtium (Indian cress, Tropaeolum majus nanum) dually blocks the COX and LOX pathway in primary human immune cells. · Phytomedicine : international journal of phytotherapy and phytopharmacology
3.PMID: 35336212 (2022) — Unraveling the Tropaeolum majus L. (Nasturtium) Root-Associated Bacterial Community in Search of Potential Biofertilizers. · Microorganisms
4.PMID: 38792178 (2024) — Antimalarial Activity of Aqueous Extracts of Nasturtium (Tropaeolum majus L.) and Benzyl Isothiocyanate. · Molecules (Basel, Switzerland)
5.PMID: 37167822 (2023) — A combination of Tropaeolum majus herb and Armoracia rusticana root for the treatment of acute bronchitis.

Tropaeolum Majus Herb

Sources & Citations

Calculate a safe dose of Tropaeolum Majus Herb

Zao Jiao

Lentibularia vulgaris

Illicium verum

Frequently asked questions

Summary

Background

Traditional uses

Active compounds

Mechanism of action

Clinical evidence

Safety & adverse effects

Evidence summary

PubMed sources

Government sources

Tropaeolum Majus Herb

Sources & Citations

Calculate a safe dose of Tropaeolum Majus Herb

Related Herbs

Zao Jiao

Lentibularia vulgaris

Illicium verum

Frequently asked questions

Summary

Background

Traditional uses

Active compounds

Mechanism of action

Clinical evidence

Safety & adverse effects

Evidence summary

PubMed sources

Government sources