The medicinal power of smooth pearl herb

Smooth pearlwort is a perennial, native plant in the Netherlands and Belgium. It is also found throughout the temperate climates of Europe and Asia. It likes nitrogen-rich and calcareous soil. You see it a lot in dune areas and dune forests. Traditionally, the plant has been used in folk medicine, especially for gout and rheumatic diseases. NB! This article is written from the personal view of the author and may contain information that is not scientifically substantiated and/or in line with the general view.

Botanical drawing smooth pearlwort / Source: Johann Georg Sturm (Painter: Jacob Sturm), Wikimedia Commons (Public domain)


  • Naming
  • Pearlwort in history
  • Active substances
  • Pearlwort and overactive thyroid gland
  • Pearlwort reduces sex hormone secretion
  • Pearlwort dissolves uric acid
  • Dose and safety


The Latin name of smooth pearlwort is Lithospermum officinale . The seeds of this plant look like white egg-shaped, smooth pearls, hence the Dutch name. In Dutch the plant is also called smooth pearl seed. Officinale means ‘from the pharmacist’s workshop’. This addition was given by Linnaeus to all plants known for their medicinal properties. Lithospermum is a combination of the Latin words litho or ‘stone’ and spermum which means ‘seed’. In German the plant is called Steinsame and in English stoneweed. That means stone seed and stone herb respectively. It would have been given this name because it works for kidney stones and the seeds resemble small white pebbles. By the way, the phenomenon that the seed looks like a stone and works for kidney stones comes from the theory of signatures; the doctrine that says that the external properties of plants reveal something about their medicinal effects on humans.

Pearlwort in history

Pliny the Elder, belonging to the ancient Romans, wrote about this plant: ‘The fruits resemble ‘symmetrical, shiny white pearls between the leaves’. It removes stones and ‘the appearance (of this plant) means (that) people can become aware of this property’. He is referring to the fact that the external characteristic says something about the medicinal effect, which later came to be called the signature theory. Furthermore, a decoction of the root was used in the past to treat measles and itching. The root was considered to purify the blood. The leaves were drunk as a painkiller. In traditional folk medicine, the seeds were pounded and pulverized to serve as a medicine for rheumatism and bladder stones.

Active substances

Of pearlwort, either the seed or the whole herb is used. It contains the following important ingredients with medicinal effects: lithospermic acid, which is a trimer of caffeic acid, fatty oil, phosphatides and mucilages.

Pearlwort and overactive thyroid gland

The TSH or thyrotropic hormone is the pituitary hormone that activates the thyroid gland. Lithospermic acid inhibits the secretion of TSH. As a result, pearlwort can be prescribed as a natural medicine by a herbalist for hyperthyroid or overactive thyroid.

Pearlwort reduces sex hormone secretion

Pearlwort is an antigonadotrope. That is a medical term for an herb that reduces the secretion of sex hormones. Secretion means: separation. There are people who claim that pearlwort reduces fertility and that it is therefore a natural contraceptive. In folk medicine, pearlwort was used as a means to promote contractions. In phytotherapy, one only assumes the antigonadotropic effect, which has a proven effect in the following indications:

  • Painful menstruation,
  • Menopausal complaints.

Pearlwort dissolves uric acid

Pearlwort is a diuretic and uric acid propellant. It may also be a drug that helps remove kidney stones. Spanish scientific research into the effectiveness of herbal medicines for kidney stones shows that pearlwort does not work well for phosphate stones, but works well for calcium stones. There is even a contraindication for phosphate stones. This is because the PH value of lithospermum officinale is slightly too high. Uric acid stones are well dissolved with smooth pearlwort. With this science in mind, this medicinal plant is used in phytotherapy

Lithospermum officinale / Source: H. Zell, Wikimedia Commons (CC BY-SA-3.0)

following indications:

  • Increased uric acid levels,
  • Prevention of gout.

Dose and safety

There are generally two ways to use slippery whitewort for therapeutic use:

  • 30 drops of mother tincture three times a day.
  • After each meal, have a glass of tea with two tablespoons of herb per glass of boiling water.

Slippery pearlwort potentially contains liver toxins in the form of pyrrolizidine alkaloids. Therefore, it should be taken in limited amounts.