Gumweed (Grindelia camporum)
Natural Standard Bottom Line Monograph, Copyright © 2013 (www.naturalstandard.com). Commercial distribution prohibited. This monograph is intended for informational purposes only, and should not be interpreted as specific medical advice. You should consult with a qualified healthcare provider before making decisions about therapies and/or health conditions.
While some complementary and alternative techniques have been studied scientifically, high-quality data regarding safety, effectiveness, and mechanism of action are limited or controversial for most therapies. Whenever possible, it is recommended that practitioners be licensed by a recognized professional organization that adheres to clearly published standards. In addition, before starting a new technique or engaging a practitioner, it is recommended that patients speak with their primary healthcare provider(s). Potential benefits, risks (including financial costs), and alternatives should be carefully considered. The below monograph is designed to provide historical background and an overview of clinically-oriented research, and neither advocates for or against the use of a particular therapy.
Asteraceae (family), August flower, California gumplant, grindelia, Grindelia camporum, Grindelia robusta, Grindeliae herba, Grindelie, gum plant, gumplant, gum weed, hardy grindelia, rosin weed, scaly grindelia, tar weed, tarweed.
Gumweed is a traditional medicine of California Native Americans, such as the Chumash people. Gumweed was used clinically from the 1880s until 1960 in the United States and the United Kingdom for the treatment of asthma, bronchitis, and poison ivy rash. Gumweed use in clinics was discontinued in 1960 when a new law required medicines to have proven efficacy in clinical trials. The plant contains grindelane diterpenoids of unknown pharmacological activity.
High quality trials supporting the use of gumweed for asthma, bronchitis, dermatitis, or any other condition are currently lacking. High quality clinical trials of gumweed are needed in these areas.
These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.
No available studies qualify for inclusion in the evidence table.
*Key to grades:A: Strong scientific evidence for this use; B: Good scientific evidence for this use; C: Unclear scientific evidence for this use; D: Fair scientific evidence against this use (it may not work); F: Strong scientific evidence against this use (it likely does not work).
The below uses are based on tradition or scientific theories. They often have not been thoroughly tested in humans, and safety and effectiveness have not always been proven. Some of these conditions are potentially serious and should be evaluated by a qualified health care professional.
Asthma, blood purification, bronchial irritation, bronchitis, burns, colds, coughs, diuretic, laxative, lice, mouth and throat inflammation, pain, rash, skin diseases, sores, tonic, wounds.
The below doses are based on scientific research, publications, traditional use, or expert opinion. Many herbs and supplements have not been thoroughly tested, and safety and effectiveness may not be proven. Brands may be made differently, with variable ingredients, even within the same brand. The below doses may not apply to all products. You should read product labels, and discuss doses with a qualified healthcare provider before starting therapy.
Adults (18 years and older)
There is no proven safe or effective dose for gumweed. Traditionally, 2 grams of chopped or powdered gumweed, or 2 milliliters of the fluid extract has been used.
Children (younger than 18 years)
There is no proven safe or effective dose for gumweed in children, and use is not recommended.
The U.S. Food and Drug Administration does not strictly regulate herbs and supplements. There is no guarantee of strength, purity or safety of products, and effects may vary. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy. Consult a healthcare provider immediately if you experience side effects.
Avoid in individuals with a known allergy or hypersensitivity to gumweed.
Side Effects and Warnings
Based on 80 years of clinical experience and thousands of years of use by California Native Americans, gumweed has a low rate of adverse effects in most healthy people, although this has not been confirmed by clinical trials. Side effects may include slowed heart rate, increased blood pressure, central nervous system depression (in large doses), or lung or kidney irritation.
Plant preparations should not be used in the eye since they may contain bacteria or fungi. Bacteria and fungi can erode the cornea leading to the need for corneal transplants or the loss of vision. Dropping a solution of gumweed in ethanol onto the eye is not recommended due to the possibility of ethanol (alcohol) irritating the eye.
Use cautiously in patients with hypertension (high blood pressure) or heart conditions. Avoid using plant preparations on open wounds unless the preparations are known to be sterile.
Pregnancy and Breastfeeding
Gumweed is not recommended in pregnant or breastfeeding women due to a lack of available scientific evidence. Taking any alcohol and gumweed preparation is not recommended in pregnant women because alcohol may cause the fetal alcohol syndrome (birth defects).
Most herbs and supplements have not been thoroughly tested for interactions with other herbs, supplements, drugs, or foods. The interactions listed below are based on reports in scientific publications, laboratory experiments, or traditional use. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy.
Interactions with Drugs
Gumweed may decrease the effects of some drugs that lower blood pressure because it may increase blood pressure. Consult with a qualified healthcare professional, including a pharmacist, as dosing may need monitoring.
Gumweed may increase the effects of some diuretics, since it may increase urine production.
Interactions with Herbs and Dietary Supplements
Gumweed may decrease the effects of blood pressure lowering herbs such as Rauwolfia serpentina. Consult with a qualified healthcare professional, including a pharmacist, as dosing may need monitoring.
Gumweed may increase the effects of diuretic herbs such as juniper.
Theoretically, gumweed may have additive effects with selenium supplements, since the plant may contain significant amounts of selenium. Too much selenium can interfere with keratin biosynthesis and has other toxic mechanisms as well.
This information is based on a systematic review of scientific literature edited and peer-reviewed by contributors to the Natural Standard Research Collaboration (www.naturalstandard.com).
Natural Standard developed the above evidence-based information based on a thorough systematic review of the available scientific articles. For comprehensive information about alternative and complementary therapies on the professional level, go to www.naturalstandard.com. Selected references are listed below.
Afifi U, Aburjai T. Antiplatelet activity of Varthemia iphionoides. Fitoterapia 2004;75:629-633. View Abstract
Anonymous. Rhus toxicodendron. Lancet 1908;172:887.
Anonymous. The therapeutic effects of Gindelia robusta. Lancet 1890;135:565.
Calderone V, Chericoni S, Martinelli C, et al. Vasorelaxing effects of flavonoids: investigation on the possible involvement of potassium channels. Naunyn Schmiedebergs Arch Pharmacol 2004;370:290-298. View Abstract
Canavan D, Yarnell E. Successful treatment of poison oak dermatitis treated with Grindelia spp. (Gumweed). J Altern Complement Med 2005;11(4):709-710. View Abstract
Heim KE, Tagliaferro AR, Bobilya DJ. Flavonoid antioxidants: chemistry, metabolism and structure-activity relationships. J Nutr Biochem 2002;13(10):572-584. View Abstract
Juzwiak S, Wojcicki J, Mokrzycki K, et al. Effect of quercetin on experimental hyperlipidemia and atherosclerosis in rabbits. Pharmacol Rep 2005;57(5):604-609. View Abstract
Kreutzer S, Schimmer O, Waibel R. [Triterpenoid sapogenins in the genus Grindelia]. Planta Med 1990;56(4):392-394. View Abstract
Spallholz JE, Hoffman DJ. Selenium toxicity: cause and effects in aquatic birds. Aquat.Toxicol 2002;57(1-2):27-37. View Abstract
Strike SS. Ethnobotany of the California Indians volume 2. Aboriginal uses of California's indigenous plants. 1994.
Timmermann BN, Hoffmann JJ, Jolad SD, et al. Diterpenoids and flavonoids from Grindelia discoidea. Phytochem 1986;25:723-727.
Zhou L, Fuentes ER, Hoffmann JJ, et al. Diterpenoids from Grindelia tarapacana. Phytochem 1995;40:1201-1207.
Copyright © 2013 Natural Standard (www.naturalstandard.com)
The information in this monograph is intended for informational purposes only, and is meant to help users better understand health concerns. Information is based on review of scientific research data, historical practice patterns, and clinical experience. This information should not be interpreted as specific medical advice. Users should consult with a qualified healthcare provider for specific questions regarding therapies, diagnosis and/or health conditions, prior to making therapeutic decisions.
March 22, 2017