Educational information, not medical advice — ask your doctor or midwife.
Marrubio is a bitter herb, known in English as white horehound. The plant is Marrubium vulgare, a member of the mint family. It grows wild on dry, waste ground in much of the world.
In Latin American home use, the dried leaves are brewed as a tea for coughs and chest colds. It is also taken as a bitter to settle the stomach and wake up hunger. Hard horehound cough sweets are the form most people meet.
The verdict on proof is simple. Human trials are few, small and weak, so its effects are not proven. Long use in tradition is not proof that it works, and not proof that it is safe.
The honest answer is that no one has shown how it works in people.
The main idea is bitterness. Bitter plants may prompt the gut to make more juices, and so help hunger. This is a long-held idea in herbal practice, not a proven effect for this plant.
For coughs, the herb is said to loosen thick mucus. That claim rests on custom and a few lab tests. Good human trials are lacking.
In animal studies, extracts have lowered blood sugar and blood pressure. In test tube work, marrubiin appears to damp down signs of swelling. Whether any of this happens in people is not established.
Most people meet marrubio as a hard cough sweet or lozenge.
Other forms: - dried leaves and flower tops, brewed as a tea - syrup, often sweetened with honey or sugar - tincture, an alcohol extract taken in drops - capsules of dried, ground herb - bitter tonics and liqueurs, where it adds taste
Sweets and syrups hold little herb and a lot of sugar. Teas and tinctures are much stronger. Labels rarely say how much marrubiin is in the product.
Horehound has a long record in old European herbal books. Greek and Roman writers named it for coughs and chest complaints.
Spanish settlers brought the plant to the Americas, where it spread and took hold. In Mexican and other Latin American home practice, marrubio tea was given for coughs, colds and stomach upset. Healers also served it as a bitter before meals.
In Germany, an expert panel backed the herb for poor appetite and mild gut upset. In Europe it is listed as a traditional herbal medicine. Those listings rest on long use, not on strong trials.
Stop and see a doctor if a cough lasts more than a week, or if you cough up blood or thick green phlegm.
Get help the same day for fever with chest pain, or for breathing that feels hard.
Stop and seek urgent care if you notice: - a racing, pounding or skipping heartbeat - fainting or severe dizziness - shaking, sweating and confusion, which can mean low blood sugar - rash, swelling of the lips or face, or trouble breathing
In the United States, horehound is allowed as a food flavouring and sold as a supplement, but the FDA ruled it not proven as an over-the-counter cough drug. In the European Union, it is registered as a traditional herbal medicine, a status based on long use rather than trials.
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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