What is Chou Wu Tong?

Chou Wu Tong is the dried leaf of a shrub. In Latin the plant is Clerodendrum trichotomum. It is also called Harlequin Glorybower.

It is one herb, not a blend. You can take it on its own or in a formula. Chinese herbalists use it mainly for aching, stiff joints and for high blood pressure.

The name means "stinking paulownia". Fresh leaves smell strong when you crush them.

In old terms, the herb is said to "dispel wind-damp". That is the old label for joint and muscle pain that gets worse in cold, wet weather. It is often paired with the herb Xi Xian Cao.

Here is the honest verdict up front. This herb has a long record of use in China, Japan and Korea. But there is very little human trial evidence.

Long use and proof of effect are two different things. A long history does not show that a herb works.

Nothing here should replace the treatment your doctor has given you. That is true above all for blood pressure medicine.

How does Chou Wu Tong work?

No one has shown how Chou Wu Tong works in people. What follows is an idea drawn from lab and animal work. It is not proof from human results.

Leaf extracts have relaxed blood vessels in animals. They have also lowered blood pressure in animals. In animal tests of swelling, they cut the swelling too.

Some of the plant's compounds dull pain signals in rats and mice. We do not know if this happens at the dose a person drinks in a tea.

Chinese medicine explains it in another way. The leaf is called cool and a bit bitter. It is said to clear "wind-damp" from the channels and calm "liver yang".

That is pattern language. It describes signs, not body chemistry. It is a useful map for a practitioner, but it is not a test of whether the herb works.

What forms does Chou Wu Tong come in?

Chou Wu Tong is nearly always taken as a decoction. That is a strong tea made by simmering the dried leaf. Other forms are less common.

Forms you may find: - Dried loose leaf, cut for simmering - Granules or "instant" extract powder that melts in hot water - Powdered leaf in capsules - Mixed formulas, most often with Xi Xian Cao, sold as tablets or granules - Liquid tinctures, mostly from Western herb suppliers

Old practice says not to boil the leaf for long when you use it for blood pressure. Long cooking is thought to weaken that effect. This is a rule of thumb, not something trials have shown.

Where it comes from:

Chou Wu Tong has been used in Chinese medicine for hundreds of years. Qing dynasty herb texts list it. They use it for joint pain and for itchy skin rashes.

Later writing adds dizziness and headache linked to high blood pressure.

In the mid-1900s, Chinese hospitals studied it as a cheap treatment for high blood pressure. They nearly always gave it with Xi Xian Cao. Those reports spread widely, but they were not well-built trials by today's standards.

The plant also grows in Japan and Korea. In Japan the young leaves are called kusagi. People boil them and eat them as a wild spring green.

Folk use for aches and skin troubles is recorded there too.

What does Chou Wu Tong help with?

• Joint and muscle pain: This is the herb's oldest and steadiest traditional use, usually for pain that feels worse in cold or damp weather. Animal studies show reduced swelling and pain responses with leaf extracts. There are no good published human trials testing it for arthritis or back pain. If you use it, treat it as an experiment on yourself and keep whatever treatment your doctor has given you.
• High blood pressure (hypertension): Chinese hospital reports from the 1950s to 1970s described drops in blood pressure when Chou Wu Tong was combined with Xi Xian Cao. These reports had no control group and no blinding, so they cannot tell a real effect from expectation or from other changes. High blood pressure usually has no symptoms and causes strokes and heart attacks over years. Do not swap prescribed medicine for this herb. If you try it alongside your treatment, check your readings at home and tell your doctor.
• Dizziness and headache with high blood pressure: Traditional texts describe the herb as calming "liver yang rising", which covers dizziness, headache and a flushed face. Practitioners still use it this way. No human trial has tested it for these symptoms. Sudden or severe headache with dizziness needs medical assessment, not a tea.
• Itchy skin rashes and eczema: A strong decoction has traditionally been used as a wash or soak for itchy, weeping skin, sometimes alongside internal use. Evidence here is traditional only. Test any wash on a small patch of skin first, and stop if the area burns, reddens or blisters.

Which foods are rich in Chou Wu Tong?

1. Kusagi: the young spring leaves of the same plant, boiled and eaten as a wild vegetable in parts of Japan
2. No common Western food contains this plant

What are the side effects of Chou Wu Tong?

• Nausea
• Vomiting, more likely with larger amounts
• Stomach ache or cramping
• Loose stools
• Dizziness or light-headedness, especially on standing up
• Dry mouth
• Drowsiness
• Skin rash or itching from an allergic reaction
• Blood pressure dropping lower than intended

Good to know:

Stomach upset is the complaint reported most often, and it usually settles when the amount is reduced or the herb is taken with food.

The effect that matters most is on blood pressure. If the herb lowers yours and you also take blood pressure medicine, you can end up dizzy, faint or falling. Older adults are at the greatest risk from a fall.

Serious harm from this herb is not well documented, but that reflects a lack of study rather than proof of safety. Stop taking it and get medical advice if you faint, develop a rash and swelling, or your skin or eyes turn yellow.

How much Chou Wu Tong should you take?

• Recommended daily: No modern, tested dose exists. The numbers below come from Chinese practice and herb listings. They do not come from trials of what is safe or what works. Amounts in common use: - Dried leaf, simmered as a tea: about 5 to 15 g a day - Powdered leaf: about 1.5 to 3 g a day - Granules or capsules: follow the label, as extract strength varies a lot Start at the low end. If you take it for blood pressure, let a trained herbalist set the amount. Then your readings can be tracked.
• Best time of day: In old practice the daily amount is split in two, morning and night. If it makes you drowsy or light-headed, take the bigger dose at night.
• With or without food: Take it with food, or just after food. The leaf can upset the stomach on its own. That is more likely with leaves picked after the plant flowers.
• Time to effect: No one knows, as it has not been measured well in people. Old practice expects joint signs to shift in one to three weeks. Judge any blood pressure change by home readings over several weeks. Do not judge it by one reading.
• How long to take it: Old use means short courses, not daily use with no end. A fair plan is two to four weeks. Then stop and look at what really changed. If joint pain has not shifted in a month, it is not likely to. For blood pressure, judge it by home readings, not by how you feel. Long-term daily use has not been studied for safety.