Educational information, not medical advice — ask your doctor or midwife.
Grindelia is a sticky yellow flower in the daisy family. Herbalists use the dried flower buds and leaves for coughs that bring up thick mucus. It is also put on the skin for the rash from poison ivy and poison oak.
The Latin name is Grindelia robusta. Other names are gumweed, tarweed and rosinweed. The buds give off a sticky gum, and that is how it got its name.
Here is the short verdict. Grindelia has a long record of use in Western herbal medicine, but no human trials support it. A long history of use is not proof that a herb works, so read the rest of this page with that in mind.
No one has shown how Grindelia works in people. The ideas below come from lab work and from what old herbal books report.
The herb is rich in resins (sticky plant gums) and saponins (soap-like plant compounds). Both can thin mucus and make a cough looser and more productive. Saponins may also make the airway lining produce more watery fluid.
Lab tests suggest some parts of the plant relax smooth muscle, the muscle that rings the airways. This has not been tested in people, so it stays a theory.
The most common forms are a tincture (an alcohol extract) and a liquid extract. Both are made from the dried flower buds and leaves.
You can also find the loose dried herb for tea, plus cough syrups and lozenges that list it as one of several herbs. Skin washes and creams are sold for itchy rashes.
The sticky resin does not dissolve well in water. That is why most makers use alcohol rather than plain tea.
Indigenous peoples of western North America used gumweed for chest complaints and for skin rashes. Settlers and doctors picked up the practice in the 1800s.
Eclectic physicians in the United States made it a standard cough remedy. It was listed in the United States Pharmacopeia from 1882 to 1926, then moved into European herbal use. Germany's Commission E later listed it for cough and bronchitis (swelling in the airways) on the strength of that record.
See a doctor if your cough lasts more than a week, brings up blood, or comes with fever, chest pain or shortness of breath. Get urgent help if you are struggling to breathe or your lips look blue. Stop the herb and call your doctor if you pass much less urine than usual, get swelling in your legs, or feel your heartbeat racing, thumping or skipping. Get emergency care for a rash with swelling of the face, mouth or throat.
Evidence grades and traditional-use labels are explained in our methodology. Nothing here is medical advice.
What it is typically used for, usual dose, cautions, and the study behind it where real trial data exists.
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