

Generic Name: Grindelia
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.
There are no high quality trials supporting the use of gumweed for asthma, bronchitis, dermatitis, or any other condition. High quality clinical trials of gumweed are needed in these areas.
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.
There is no proven safe or effective dose for gumweed in children, and use is not recommended.
Avoid in individuals with a known allergy or hypersensitivity to gumweed.
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.
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).
Gumweed may decrease the effects of some antihypertensives (drugs that lower blood pressure), since 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.
Gumweed may decrease the effects of antihypertensive (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, and was peer-reviewed and edited by contributors to the Natural Standard Research Collaboration (www.naturalstandard.com): James David Adams, Jr., PhD (USC School of Pharmacology); J. Katherine Bryan, BA (Natural Standard Research Collaboration); Nicole Giese, MS (Natural Standard Research Collaboration); Shaina Tanguay-Colucci, BS (Natural Standard Research Collaboration); Wendy Weissner, BA (Natural Standard Research Collaboration).
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Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.


