Most people do not realize the illustrious medicinal history behind the white oak -- its bark has been used as an herbal remedy for centuries, and there is a renewed interest now that modern science allows a better understanding of the active ingredients. White oak bark contains 15 to 20 percent tannins, which is responsible for much of the beneficial effects. But it also contains iron, potassium, vitamin B12 and other nutrients, which may play a role in the treatment of certain conditions. White oak bark's safety and effectiveness has not been proven, so consult your doctor before use.
White oak bark can be roasted, ground and infused into warm water and taken internally as an astringent. In conditions where there is bleeding, discharge or other secretions, the astringent will cause the vessels that carry the fluid to contract to the point that the fluid can no longer pass. Although this stops the leakage, it does not treat the underlying disorder, so is seen as a temporary treatment of symptoms instead of a cure of the disorder. White oak bark has been used in this manner to treat diarrhea, nosebleeds, heavy menstrual flow and vomiting.
When taken internally, white oak bark acts as a diuretic, flushing excess fluid from the body. Although this was initially only a side effect, traditional herbalists took advantage of this property to help flush out kidney stones and bladder infections by increasing urinary output. It is thought that this mobilization of body fluids can help restore function to the liver and kidneys, as well as clear mucous congestion. Again, the white oak bark doesn't treat the underlying condition, but can make the symptoms temporarily more tolerable.
The tannins in white oak bark can help flush parasites from the body when taken internally. As a parasiticide and anthelmintic, it kills adult worms, and the diuretic property helps draw fluid to flush them out in the stool. The tannins also have strong antiseptic properties that help make it difficult for bacteria to permeate tissues, preventing infection from occurring or advancing. This property combines with the diuretic property to make white oak bark a traditionally effective treatment for bladder infections.
The same white oak bark decoction that is used internally can also be used topically as a wash and wound protectant. It helps stop bleeding, and forms a protective antiseptic layer to allow healing to occur safely without risk of infection. Topical application extends to douches and hemmorhoid washes, both of which also take advantage of antiseptic properties. Pastes made from white oak bark, water and flour can help draw out bee stingers and splinters due to the astringent nature.