Mikania glomerata (Mikania glomerata): Benefits, Dosage, Safety & Evidence

Frequently asked questions

How does Mikania glomerata work as an expectorant?

Mikania glomerata contains coumarin, mikanolide, and sesquiterpenes that contribute to its medicinal effects. The coumarin content is primarily responsible for the plant's expectorant properties, helping to loosen and clear mucus from the respiratory tract. Additionally, these compounds demonstrate antimicrobial activity against certain pathogens. The plant's anticoagulant effects are also attributed to its coumarin content. Evidence level: C (preliminary research).

Can I take Mikania glomerata with blood thinners?

Mikania glomerata should not be taken with blood-thinning medications such as warfarin, heparin, or antiplatelet drugs. The plant contains natural coumarin compounds that possess anticoagulant properties, which can enhance the effects of pharmaceutical blood thinners and increase the risk of bleeding. This interaction is well-documented in traditional use reports. Patients on anticoagulant therapy should avoid this herb entirely and consult a healthcare provider before use.

What is the recommended dosage of Mikania glomerata for adults?

For adults, the typical dosage of Mikania glomerata is 2-4 ml of tincture taken up to three times daily, or 5-10 grams of dried herb prepared as a tea. These recommendations are based on traditional Brazilian medicinal practice rather than standardized clinical trials. Dosage should be adjusted based on individual response and under guidance from a qualified healthcare practitioner. Evidence level: Traditional use.

Is Mikania glomerata safe during pregnancy?

Mikania glomerata is considered unsafe during pregnancy and should be avoided. The plant contains coumarin compounds that may cross the placenta and potentially affect fetal development or cause bleeding complications. Traditional contraindications explicitly warn against use by pregnant women. Breastfeeding women should also avoid this herb due to insufficient safety data. Always consult a healthcare provider before using any herbal supplement during pregnancy.

What is Mikania glomerata used for in traditional medicine?

Mikania glomerata, native to Brazil, is traditionally used for respiratory conditions including coughs, bronchitis, and asthma due to its expectorant properties. In Brazilian folk medicine, it is also applied as a remedy for snake bites and as an antimicrobial agent. The herb is known locally as 'guaco' and has been used for centuries. Current evidence supporting these uses is limited to preliminary research (Evidence level: C) and traditional documentation.

What are the side effects of Mikania glomerata?

Common side effects of Mikania glomerata include gastrointestinal upset such as nausea, vomiting, or diarrhea. Due to its coumarin content, the herb may cause increased bleeding, particularly in individuals with bleeding disorders or those taking anticoagulant medications. Prolonged use or high doses may increase the risk of adverse effects. Anyone experiencing unusual bleeding or bruising should discontinue use and seek medical attention immediately.

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

Mikania glomerata, popularly known as guaco, is a Brazilian medicinal plant primarily used to treat respiratory conditions [PMID:20636868, PMID:40283987].

Background

Mikania glomerata is a native climbing plant from Brazil [PMID:28627377]. It is often used interchangeably with Mikania laevigata, although they possess different chemical profiles [PMID:28926862, PMID:304150 laevigata].

Traditional uses

In Brazilian traditional medicine, it is used for upper respiratory problems including bronchitis, pleurisy, colds, flu, coughs, and asthma [PMID:20636868]. Brazilian Indians have an ancient tradition of using guaco for snakebites [PMID:20636868].

Active compounds

Major constituents include coumarin (2H-1-benzopyran-2-one), o-coumaric acid, and diterpenes such as ent-kaurenoic acid [PMID:22932215, PMID:16755468, PMID:28627377]. Other identified compounds include methyl cinnamate, hexadecanoic acid, and various sesquiterpene lactones of the germacranolide type [PMID:25202336, PMID:11261581].

Mechanism of action

Anti-inflammatory effects may involve the suppression of neutrophil migration, which is dependent on the production of cytokines interleukin-1beta and tumour necrosis factor-alpha, as well as a nitric oxide-dependent mechanism [PMID:19703354].

Clinical evidence

Evidence BGeneral Safety

A phase I clinical trial evaluated the safety of M. glomerata oral solution in healthy volunteers over two weeks of use [PMID:37562463]

Evidence CRespiratory Diseases

Used as a natural bronchodilator, expectorant, and cough suppressant for upper respiratory problems [PMID:20636868]

Evidence DEndodontic/Cariogenic Bacteria

Ent-kaurenoic acid-rich extracts showed antibacterial activity against bacteria responsible for dental caries and endodontic infections [PMID:28627377, PMID:27316976]

Evidence DAllergic Pleurisy

An ethanolic extract fraction (MG1) significantly reduced plasma exudation and neutrophil/eosinophil infiltration in ovalbumin-induced allergic pleurisy [PMID:10432203]

Evidence DSarcoma 180 (Mouse Model)

Complexes of ent-kaurenoic acid with beta-cyclodextrin demonstrated antitumor activity in a mouse model [PMID:36529360]

Safety & adverse effects

A phase I trial monitored adverse events in healthy volunteers [PMID:37562463]. Some evidence suggests that extracts from M. glomerata cultivated in conventional systems may be genotoxic, whereas organic systems showed different results [PMID:31258003].

Pregnancy & lactation

A study in hypertensive rats analyzed the toxic effects of M. glomerata administration during the gestational period [PMID:26894037].

Drug interactions

There is theoretical concern that guaco may interact with anticoagulants due to its coumarin content, although in vitro studies on M. laevigata sought to evaluate this [PMID:31815870].

Evidence summary

The evidence is primarily preclinical (animal and in vitro studies) with limited clinical data consisting of one phase I safety trial. Most evidence is categorized as level D or C.

PubMed sources

1.PMID: 40283987 (2025) — Biological Activities of Mikania glomerata and Mikania laevigata: A Scoping Review and Evidence Gap Mapping. · Pharmaceuticals (Basel, Switzerland)
2.PMID: 20636868 (2010) — Scientific evidence for Mikania laevigata and Mikania glomerata as a pharmacological tool. · The Journal of pharmacy and pharmacology
3.PMID: 11261581 (2001) — Germacranolides from Mikania guaco. · Phytochemistry
4.PMID: 22932215 (2012) — Preparation of dry extract of Mikania glomerata Sprengel (Guaco) and determination of its coumarin levels by spectrophotometry and HPLC-UV. · Molecules (Basel, Switzerland)
5.PMID: 16755468 (2006) — LC characterisation of guaco medicinal extracts, Mikania laevigata and M. glomerata, and their effects on allergic pneumonitis.

Mikania glomerata

Sources & Citations

Calculate a safe dose of Mikania glomerata