St. John's wort is a traditional medicinal plant. St. John's wort oil is a well-known natural extract that our grandmothers often put to good use in home remedies. In addition to calendula macerate, it has become one of the most popular homemade skincare preparations in Slovenia.
Its effects are especially beneficial in treating damaged skin, relieving burns and treating sensitive or stressed skin.
Like many others, St. John's wort is a medicinal herb that also has certain side effects. It can influence the effectiveness of certain medicines and can increase the skin's sensitivity to sunlight.
In scientific circles, the opinions on the dangers of sun exposure after the application of St. John's wort oil are divided. This is because while St. John's wort is phototoxic, the same doesn’t apply to its extracts.
What is phototoxicity?
Phototoxicity is a reaction that results when a particular substance comes in contact with light. It causes damage on a cellular level that manifests itself as burns, redness, peeling skin or dark discoloration of the skin (hyperpigmentation).
Phototoxic reactions can be caused by different substances, such as particular medicines, contact with some plants, certain essential oils and the hypericin found in St. John's wort. The largest amounts of hypericin can be found in the buds and flowers of St. John's wort, while the leaves hold smaller amounts of it. Hypericin is known as the most phototoxic natural compound.
The phototoxicity of hypericin can also be used to positive effect. It is used to great benefit in photodynamic therapy to treat different dermatological problems, such as eczema, psoriasis and melanoma. Here, hypericin is applied to the skin and activated by light.
St. John's wort oil (Hyperici Oleum) is a simple preparation extracted by soaking St. John's wort flowers in olive oil. It holds a special place in Slovenian herbalism and has always had a rich tradition of application. The mixture must be placed in a sunny position during the process, as the sun is crucial for the extraction of hypericin. In 3 to 6 weeks, the oil will turn reddish, and after that, it can be strained and is ready to use.
Can phototoxic hypericin be found in St. John's wort oil?
Scientific literature has been recording the lack of hypericin in St. John's wort oil for a while now. Under the influence of sunlight during the maceration process, hypericin is converted into lipophilic derivatives, which give St. John's wort oil its reddish color.
Is St. John's wort oil phototoxic?
St. John's wort oil is not phototoxic and does not cause damage or burns to the skin. You do not have to avoid sunlight after using St. John's wort oil or products that contain it, but it should be noted that St. John's wort oil does not protect you against the harmful effects of sunlight.
With St. John's wort, more attention should be paid to internal use, especially if your skin is sensitive or if you are taking any medication that could interact poorly with the herb or its extracts.
Including St. John's wort oil in after-sun care products is extremely beneficial due to its anti-inflammatory and antibacterial effects. It can accelerate damaged skin regeneration, alleviate burns, and is also exceptional in alleviating some other skin problems.
Source: Dr. Petra Ratajc; https://petraratajc.com/2018/06/17/sentjanzevo-olje/