What is Bai Zhi?

Bai Zhi is a dried root. It comes from a plant called Angelica dahurica. Chinese herb shops sell it in slices or as a powder.

Herbalists use it most often for a stuffy nose, sinus pain and a headache across the brow. It is also used for toothache and for sore, swollen skin. It is almost always mixed with other herbs, not taken alone.

Here is the short verdict. Bai Zhi has a long record of use, but good human trials of the single herb are hard to find. Long use is not proof that a herb works, and that point applies to every claim on this page.

How does Bai Zhi work?

No one has shown how Bai Zhi works in the human body. Lab and animal work gives us some clues, but clues are not proof.

In lab tests, parts of the root calm swelling and ease pain signals. Some of its compounds also kill germs in a dish. That does not tell us what happens after you drink a cup of the tea.

In Chinese medicine the herb is said to be warm and drying. It is used to open a blocked nose and to move pain out of the head and face. That is a way of sorting herbs by use, not a test of what they do inside you.

What forms does Bai Zhi come in?

Bai Zhi is sold in a few plain forms.

Dried slices are the most common. You simmer them in water to make a strong tea, called a decoction.

You can also find ground powder, capsules, tinctures (a liquid made with alcohol) and ready-made pill blends. In China it turns up in many packaged nose and sinus formulas. Some skin creams and washes use it too.

Where it comes from:

Bai Zhi is an old, core herb in Chinese medicine. It is listed in the Shennong Bencao Jing, a herb text from roughly two thousand years ago.

It has stayed in daily use ever since, mostly in blends for the nose, head and face. It is also used in Korean and Japanese herb practice.

What does Bai Zhi help with?

• Stuffy or blocked nose: This is the most common use. Bai Zhi sits in many Chinese blends for a blocked nose and post-nasal drip. The trials that exist test the whole blend, not this one herb, so we cannot say how much of any result came from Bai Zhi.
• Sinus pain and pressure: Herbalists pair it with Xin Yi Hua and Cang Er Zi for this. Support is from long use and from small lab studies on swelling. Good human trials of the single herb are hard to find.
• Headache across the forehead and brow: This is a classic use in old texts. It is the herb picked when pain sits above the eyes. No solid human trial tests Bai Zhi alone for headache.
• Toothache and face pain: Old texts use it for aching teeth and jaw. Lab work shows some pain-easing action in animals. There is no human trial that backs this up, so treat it as tradition only.
• Common cold with chills: It is used early in a cold, when you feel cold and your nose runs. It is always part of a blend here. Evidence is traditional, not tested.
• Boils and sore, swollen skin: Powdered root has been used in pastes and washes for boils. Lab tests show some germ-killing action in a dish. Skin use also raises the risk of a sun rash, so cover the area.

Which foods are rich in Bai Zhi?

1. Celery: not a source of the herb, but it holds the same kind of sun-sensitising compounds
2. Parsnip: same plant family, same type of compounds
3. Grapefruit: holds compounds that also slow the same liver enzymes

Practical Tips:

You do not get Bai Zhi from food. These foods only matter because they act on the same paths.

What are the side effects of Bai Zhi?

• Skin burns or turns red in the sun more easily than normal
• Rash or itchy skin
• Upset stomach or nausea
• Dry mouth and dry throat
• Loose stools
• Headache or a light, dizzy feeling
• Allergy, more likely if you react to celery, parsnip or carrot

Good to know:

Most people who take normal amounts for a short time have no trouble. When side effects do show up, they are mild and fade once you stop.

The sun rash is the one to watch. The plant compounds make skin burn faster in sunlight and in tanning beds. Wear a hat, cover up, and use sun cream while you take it.

Stop the herb and call a doctor if you get a bad burn, a blistering rash, yellow skin or yellow eyes.

How much Bai Zhi should you take?

• Recommended daily: No safe dose has been set by trials. What follows is the usual range used by herbalists, not a proven dose. Dried root for tea: 3 g to 10 g a day, simmered in water. Powder: 1 g to 3 g a day. Made-up pills and tinctures: follow the label, and do not go above it. Use the lowest amount that helps. Do not stack two products that both hold Bai Zhi.
• Best time of day: Split the daily amount into two or three doses, spread across the day. Take the last dose well before bed if it keeps you awake. Try not to take it right before a long spell in strong sun.
• With or without food: Take it with food or just after a meal. This is a warm, drying herb and can upset an empty stomach.
• Time to effect: If it helps a stuffy nose, people tend to notice within a day or two. If nothing has changed in a week, it is not working for you.
• How long to take it: Short spells only. Most herbalists use it for a few days to two weeks, while a cold or sinus flare lasts. Stop and think again after two weeks. If your nose or head pain is no better by then, see a doctor.