What is Asthma weed (snake weed)?

Asthma weed is a small hairy weed that creeps flat along the ground. Botanists call it Euphorbia hirta. Yoruba speakers call it emi ile.

West African home medicine used it for coughs, wheezing, worms and loose stools. Long use in a tradition is not proof that a plant works. It is also not proof that it is safe.

Here is the honest verdict up front. Nearly all the research sits in test tubes and animals. We found no reliable human trials, so treat every claim on this page as unproven.

One hazard is worth knowing before you read on. A broken stem leaks milky white sap. That sap stings skin and can badly damage an eye.

How does Asthma weed (snake weed) work?

No one has shown how asthma weed acts inside the human body. Everything below comes from lab and animal work.

In test tubes, extracts relax strips of airway and gut muscle taken from animals. That finding is part of why the plant kept the name asthma weed. Whether it opens airways in a living person is not known.

In rodents, extracts have slowed the gut and reduced diarrhoea. Cell studies also point to some calming of inflammation. These are early signals, not proof of a human effect.

In laboratory tests, extracts slow the growth of some bacteria, fungi and parasites. Whether that happens inside a person has not been shown.

Animal studies have also reported lower blood sugar and lower blood pressure. The doses used were often high. Human data to match them does not exist.

What forms does Asthma weed (snake weed) come in?

Most use is homemade rather than shop-bought.

Forms you may meet: - the fresh whole plant, boiled in water as a decoction or tea - dried, crushed leaf sold loose or in tea bags - capsules or loose powder from herbal suppliers - tinctures, which are alcohol extracts - fresh sap or crushed leaf pressed onto skin - juice from the fresh plant, sometimes mixed with honey

Quality control is weak across all of these. Products are rarely tested by an outside lab. The label may not match what is inside the pack.

Mix-ups are a real risk too. Many Euphorbia species look alike as young plants. Buying a named, batch-tested product lowers that risk but does not remove it.

Where it comes from:

Asthma weed has a long record in West African home medicine. Yoruba users knew it as emi ile. Healers boiled the whole plant and gave the liquid for coughs, wheezing, worms and loose stools.

The plant spread across the tropics and picked up similar roles. Healers in India, the Philippines and the Caribbean used it for breathing trouble and dysentery. The sap was dabbed on warts, boils and skin sores.

Some colonial-era pharmacy books listed it for asthma and bronchitis. Those entries record what people did at the time. They are not a guide to using the plant today.

What does Asthma weed (snake weed) help with?

• Asthma and wheezing: This is the use the plant is named for, and it is the least safe one to copy. West African and Asian healers gave the boiled plant for tight, wheezy breathing. The only supporting work is in test tubes and animals, where extracts relax airway muscle. There is no human trial showing it helps asthma. Asthma can kill. Never swap a prescribed inhaler for this plant.
• Cough and chest colds: Tradition used warm decoctions to loosen a cough. Honey was often added. No human study supports this. Any relief may come from the warm drink and the honey. A cough lasting more than three weeks needs a doctor, not a herb.
• Diarrhoea and dysentery: This is the best-supported use in animal work, which is still not the same as proof in people. Rodent studies show slower gut transit and less diarrhoea. Traditional healers used it for watery stools and for blood-streaked dysentery. Human trial evidence is missing. Fluids matter more than any herb here. Blood in the stool or a high fever needs medical care.
• Intestinal worms: Decoctions were given to children and adults to clear worms. That practice is widespread across the tropics. In test tubes, extracts harm some worm species. No human trial shows that it clears worms from a person. Modern worm medicines are cheap, tested and taken as a single dose. They are the better option.
• Boils, warts and skin sores: The fresh sap was dabbed straight onto warts and boils. The sap is caustic, meaning it burns tissue. That burn may be why warts sometimes looked smaller. It can also leave a scar or a wound that gets infected. No human trial has tested this. Keep it far from your eyes.
• Hay fever and itchy eyes: Some traditions used the plant for sneezing and watery eyes. Cell studies show it can damp down histamine release, a step in allergy. That is lab work only. No human evidence backs it. Never put any form of this plant in your eye.

Which foods are rich in Asthma weed (snake weed)?

Asthma weed is a medicinal herb, not a food. It is not a normal part of any diet, and no everyday food contains it.

What are the side effects of Asthma weed (snake weed)?

• Nausea and vomiting
• Stomach cramps
• Loose stools
• Burning in the mouth and throat
• Skin rash or blistering where the sap touches
• Severe eye pain and eye damage if sap gets in the eye
• Drowsiness or light-headedness
• Allergic reaction, with rash, swelling or wheeze

Good to know:

Stomach upset is the common one, and strong homemade decoctions bring it on most often. It usually settles once you stop.

The serious hazard is the milky sap. In the eye it can cause burns, corneal damage and lasting sight loss. This is reported in medical case reports for several Euphorbia species.

Allergic reactions are less common but can be severe. Swelling of the lips, tongue or throat is a medical emergency.

How much Asthma weed (snake weed) should you take?

• Recommended daily: There is no tested, safe dose for this plant. No human trial has set one. Capsule labels from herbal suppliers often list 300 to 500 mg of dried leaf powder. That figure reflects what makers print, not what research supports. It is not advice for you. Traditional decoctions vary hugely between households. Strength depends on how much plant goes in the pot and how long it boils. That is one reason stomach upset is common. If you are set on trying it, speak to a doctor or pharmacist first, especially about your other medicines.
• Best time of day: Time of day does not matter. No study has compared morning with evening use. One practical note: some people feel drowsy after taking it. If you notice that, do not drive.
• With or without food: Taking it with food may ease stomach upset. Nausea and cramps are the most common complaint. No study has compared with food against without food. This is practical advice, not a research finding.
• Time to effect: Be ready for it to do nothing. That is a fair expectation, given the state of the evidence. Traditional users expected gut effects within a few hours. Nothing confirms that in a trial. If you take it for breathing trouble and feel no better, do not wait. Use your inhaler and get help.
• How long to take it: Traditional use was short. People drank it for a few days during an illness, then stopped. No study has looked at long-term safety in people. The plant contains shikimic acid and spurge-family irritants, and the effect of taking these for months is unknown. So a long daily course cannot be called safe. If a problem lasts more than a few days, that is a reason to see a doctor.