What is Shen Tong Zhu Yu Tang?

Shen Tong Zhu Yu Tang is a Chinese herbal formula. The name means "move stuck blood and stop body pain." Practitioners give it for aches that have lasted weeks, months or years.

It is used most often for pain in the low back, hips, legs, shoulders and joints. In Chinese medicine, that pain is put down to blood that is "stuck" and no longer flowing well. The mix is meant to get things moving again.

Here is the honest verdict. The formula has been used since 1830, but long use is not proof that a remedy works. We could not find good human trials of it, so no one can say how well it works, or for whom.

How does Shen Tong Zhu Yu Tang work?

How this formula works has not been tested in people. What follows is the traditional idea, plus hints from lab work.

In Chinese medicine, the mix is said to move blood and qi (the body's vital energy). It is also said to open the channels, the paths that pain is thought to block. Some herbs are chosen to steer the mix toward the limbs and low back.

In modern terms, single herbs from the mix have been studied in test tubes and in animals. Some slow blood clotting. Some calm swelling and dull pain signals in nerve cells.

That lab work is a starting point, not an answer. It does not tell us what a whole formula does inside a person at the doses people take. Treat any story about the "mechanism" as a theory for now.

What forms does Shen Tong Zhu Yu Tang come in?

Most people meet it in one of four forms.

Raw herbs come as a paper bag of cut roots, seeds and flowers. You boil them into a decoction (a strong herbal tea) and drink it warm.

Granules are the common modern form. The tea is dried into a powder that you stir into hot water. Pills and tablets are also sold, and they are the easiest to carry.

A practitioner may also write you a custom version. They add or drop herbs to fit your case, so your mix may not match the label of a shop product.

Where it comes from:

The formula comes from Yi Lin Gai Cuo, or "Correcting the Errors of Medicine," published in 1830. The author was Wang Qingren, a Chinese doctor known for his focus on blood.

Wang wrote a set of "drive out stuck blood" formulas, each aimed at a different part of the body. This one was his choice for pain in the trunk and limbs.

It is still taught in schools of Chinese medicine today and is stocked by most herb suppliers.

What does Shen Tong Zhu Yu Tang help with?

• Long-term low back pain: This is the classic use. The old texts point the formula at back pain that has dragged on and sits in one spot. We found no human trial we can name, so this use rests on tradition.
• Sciatica (nerve pain that runs down the leg): Practitioners often pick this mix for pain that shoots from the hip down the back of the leg. Niu Xi is in the formula to steer the herbs downward. Good trials in people are lacking.
• Joint and limb aches that will not shift: Qin Jiao and Qiang Huo are the herbs here for sore joints and limbs. Tradition uses the mix for aches that are worse after rest and easier with gentle movement. It does not repair a worn or damaged joint.
• Shoulder and neck pain: Tradition uses it for a stiff, sore shoulder that has lasted months. In practice it is often given alongside acupuncture or massage. There is no solid trial support for this use.
• Pain left over after an old injury: Chinese medicine sees old bruising as stuck blood, and this formula aims at that idea. Practitioners use it when pain lingers long after the injury has healed. Again, this comes from tradition, not from trials.
• Widespread body pain: Some practitioners use it when aches move around the whole body. This is a looser fit for the formula. See a doctor first, because widespread pain has many causes and some of them need tests.

Which foods are rich in Shen Tong Zhu Yu Tang?

1. Licorice sweets and licorice tea: they add to the licorice already in the mix, so keep them low
2. Dang gui soups sold in Asian groceries: the same root, so count it in your daily total
3. Safflower oil and safflower food colour: the same plant, but food amounts are far smaller than the herb dose
4. Peach kernels sold as a snack: do not eat them in bulk while you take this formula

What are the side effects of Shen Tong Zhu Yu Tang?

• Loose stools or diarrhoea
• Nausea or a churning stomach
• Belly pain or cramps
• Bruising more easily than usual
• Nosebleeds, or gums that bleed when you brush
• Heavier or longer periods
• Rash or itching
• Swollen ankles, higher blood pressure, or low potassium (a low level of a salt your heart needs) after weeks of use, from the licorice in the mix

Good to know:

Most complaints are mild and fade when you stop. Stomach upset is the one people report most.

Bleeding is the main thing to watch. Several herbs here slow clotting, so odd bruises and nosebleeds can turn up.

Licorice is the other watch point. Weeks of daily use can raise blood pressure and lower potassium. Stop and ask a doctor if your ankles swell or you feel weak and crampy.

We do not have good safety data on the whole formula. That means rare harms may exist that no one has counted yet.

How much Shen Tong Zhu Yu Tang should you take?

• Recommended daily: No trial has set a dose for this formula. What follows is common practice, not a tested amount. Raw herbs: about 60 to 100 g of the dry mix, boiled once and drunk in two cups over the day. Granules: about 6 to 12 g a day, split into two doses. Pills: follow the label, since strength differs a lot by brand. A practitioner will often set a different amount for you. Their number wins over the label.
• Best time of day: Split the day's amount into two doses, one in the morning and one in the early evening. Drink it warm. Traditional practice is to take it between meals.
• With or without food: Between meals is the traditional advice, on a fairly empty stomach. If it makes you feel sick or gives you belly pain, take it with a little food instead.
• Time to effect: Practitioners usually expect some change in one to two weeks. No trial has measured this, so treat the timing as a rough guide.
• How long to take it: Plan for a short course, then take stock. Two to four weeks is a normal first run. If your pain has not budged by then, stop and rethink. More weeks of a mix that is doing nothing only adds risk. Do not take it daily for months on end without a check-up. The licorice in the mix is the reason, as it can push blood pressure up over time.