Educational information, not medical advice — ask your doctor or midwife.
Blumea balsamifera is a tall, strong-smelling shrub from South and Southeast Asia. In the Philippines it is called sambong. In Chinese medicine it is known as ai na xiang.
The leaves are dried for tea or pressed into tablets. The plant also yields ngai camphor, a sharp-smelling oil used on the skin. Healers used it mainly to make people pass more urine.
The main traditional uses are kidney stones, fluid build-up, colds and sore joints. Human evidence is thin. A few small, weak studies hint at a mild water pill (diuretic) effect, and little else is settled.
Long traditional use is not proof that a plant works. It is also not proof that it is safe. Read the safety section below before you decide.
The clearest claim is simple: it makes you pass more urine.
Small human studies in the Philippines did report more urine output after sambong leaf. The studies were small and poorly controlled. So the effect looks mild and is not firmly proven.
In animal studies, leaf extracts raised urine volume and salt loss. The plant's flavonoids are thought to drive this. How that works in a human kidney is not mapped.
In test tubes, leaf extracts slowed the growth of calcium oxalate crystals. Those crystals form many kidney stones. Whether the same thing happens inside a person is not established.
Lab and animal work also reports effects on bacteria, on swelling and on blood sugar. These are cell and animal findings only. They do not show that the tea treats an infection or any disease.
The essential oil owes its smell to borneol, a camphor-type compound. On skin it feels cooling. That feeling is not evidence of healing underneath.
You will most often meet it in these forms:
- Dried leaf tea or a boiled leaf decoction. - Tablets and capsules of leaf extract, sold widely in the Philippines as sambong.
- Fresh or wilted leaves laid on the skin as a poultice. - Leaf added to a warm bath or steam inhalation. - Ngai camphor essential oil and camphor-type balms, for skin use only.
Tablet products are the most consistent. Homemade teas vary batch to batch.
The essential oil is a different thing from the tea. It is far stronger and is not for swallowing.
Sambong has a long, well recorded place in Philippine folk medicine. Healers brewed the leaves for people passing little urine, or thought to have stones.
In traditional Chinese medicine the plant was known as ai na xiang. Practitioners used it for cold, damp conditions and for aches. The distilled camphor was prized as a trade good.
Across Thailand, Vietnam, Malaysia and Indonesia, women were given warm leaf baths after childbirth. Leaves were also laid on wounds and boils, and burned to keep insects away.
These records show steady, widespread use over centuries. They tell you what people believed, not what the plant does.
Stop and see a doctor if you feel faint, get muscle cramps, or notice a fast or irregular heartbeat.
Stop and get help the same day if you get a rash, swelling of the face or lips, or trouble breathing.
Go to an emergency department if you have severe back or side pain, blood in your urine, a fever with chills, vomiting, or you cannot pass urine at all. These point to a blocked or infected kidney.
If anyone swallows camphor oil, call emergency services or a poison centre at once, even if they seem fine.
In the Philippines, sambong is registered with the Food and Drug Administration as a herbal medicine and sold over the counter. In the United States, United Kingdom, European Union and Australia it is sold as a supplement or herbal product, with no approval as a medicine.
Evidence grades and traditional-use labels are explained in our methodology. Nothing here is medical advice.
What it is typically used for, usual dose, cautions, and the study behind it where real trial data exists.
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