Shang Lu

What is Shang Lu?

Shang Lu is the dried root of pokeweed. In the West the same root is called pokeroot. It is a single herb used on its own, not a blend.

Chinese medicine uses it to push water out of the body. Healers gave it for swelling in the legs or belly. They also spread it on the skin for boils and hard lumps.

The root is toxic. It can cause harsh vomiting, cramps, and worse. No human trial shows that it helps any illness, and a long history of use is not proof that a herb works.

How does Shang Lu work?

Shang Lu works by making you very sick, and that is the whole of what we know.

The root holds soap-like plant compounds called saponins. In lab tests they strip the lining of the gut. That is why the herb causes vomiting and watery stools.

Old texts read this loss of fluid as "draining water" from a swollen body. Losing fluid that fast can drop your blood pressure. It can also drop your potassium, a salt your heart needs.

The root also holds a protein called pokeweed mitogen. It stirs up white blood cells in a test tube. No one has shown that this does any good in a living person.

What forms does Shang Lu come in?

Shang Lu is sold as dried root slices. A practitioner boils them into a strong tea called a decoction.

Most Chinese suppliers treat the root with vinegar first. This is meant to cut the harshness. It does not make the herb safe.

It also comes as a powder for a paste used on the skin. Homeopathic Phytolacca drops are a separate product; they are diluted so far that they are not the same thing as this herb.

Where it comes from:

Shang Lu is an old herb with a clear warning attached to it.

It appears in the Shen Nong Ben Cao Jing, a Chinese herb book from about 200 CE. That text places it in the lowest of three classes. Those are the strong, toxic herbs, used in small doses and for a short time only.

In the southern United States the same plant was used in folk medicine and eaten as a boiled green. Poisonings from both uses are well recorded.

What does Shang Lu help with?

• Swelling from fluid build-up (edema): This is the classic Chinese use. The herb forces out fluid by causing heavy diarrhoea and urine loss. No trial has tested it against a dummy treatment, and modern water pills do the same job far more safely.
• Fluid in the belly (ascites): Old texts used it for a swollen, tight belly. Ascites is usually a sign of serious liver or heart disease. Treating it with a toxic purging herb is risky and is not supported by any trial.
• Hard constipation, in old texts: The root empties the bowel because it irritates the gut lining. That is poisoning, not treatment. Gentle, tested options exist and should be used instead.
• Boils and skin sores, used on the skin: Paste made from the root was laid on boils and lumps. The root is a skin irritant and can cause burning and blisters. No human trial supports this use.
• Swollen neck glands, in old texts: Chinese and American folk healers both used the root for swollen glands. Swollen glands can signal infection or cancer. See a doctor rather than treating this at home.

What are the side effects of Shang Lu?

• Vomiting, often hard and repeated
• Watery diarrhoea, sometimes with blood
• Belly cramps and burning in the mouth and throat
• Loss of body fluid (dehydration)
• Low potassium, a salt your heart and muscles need
• Low blood pressure, dizziness and fainting
• A slow, fast or uneven heartbeat
• Headache, blurred sight and confusion
• Fits (seizures)
• Slow, weak breathing
• Skin burning, redness or blisters where the paste is laid
• Miscarriage or harm to a pregnancy
• Death, reported after large doses and in children

Good to know:

Stomach and bowel upset is not a rare side effect here — it is what the herb does to nearly everyone who takes it.

The serious effects come next. Heavy fluid loss can drop your blood pressure and your potassium. That can upset your heart rhythm and, in bad cases, lead to fits or death.

Children are at highest risk. Deaths have been reported in children who ate the raw root or the berries.

Options to discuss with a clinician

If swelling or fluid build-up is what draws you to Shang Lu, gentler options are worth raising. Dandelion leaf and corn silk are mild traditional water pills (diuretics) with far less risk of poisoning. You could bring these names to a clinician and ask whether either one suits your case.

Swelling can also be a sign of heart or kidney trouble. A doctor can look for the cause first, which matters more than any herb choice. You might also ask about simple steps, such as less salt or resting with your legs raised.

Graded pages for the options named above:

• Corn Silk — evidence grade C, traditional tier T2