St John’s Wort

Hypericum perforatum

NL: St Janskruid / 
F: Millepertuis

St John’s Wort (SJW) is another powerful herb with a long history as folk medicine. In our days St John’s Wort got great media attention for aiding in the treatment of those suffering from depression, being known as the “natural prozac”

Long before SJW got to be used to treat depression, it was considered to be a “herb that chases the evil spirits away” as it was used to treat various types of insanity attacks. Paracelsus was whom mentioned it for the first time for treatment of a wide range of psychotic symptoms. Even though it is not yet clear to modern medicine how exactly SJW works on the nervous system, its nervine action is recognized by herbalists around the world.

Its most widespread use in herbal medicine is in healing wounds, bruises, sunburn, herpes, skin ulcers and inflammations. Most of its skin healing abilities are attributed to its properties as analgesic, antiviral, antibacterial, antiseptic and astringent. In poultices, oils, salves and ointments it is used to heal many skin problems. 

As expectorant it is also employed to treat conditions of the respiratory tract. It is also used to help healing bladder problems, such as urine incontinence.

SJW should not be used by pregnant women. People using St John’s Wort are advised to avoid direct exposure to sunlight SJW, especially during summertime when the U.V. levels ar emuch higher, as it increases photosensitivity. 

Another word of caution goes to people taking prescription drugs: SJW contains chemical compounds that may block or alter the effect of several drugs. For a more extended list of interactions between some prescription drugs and SJW, click here. 

The (fresh) flowers are the most active part of the plant and they can be harvested from June to August. They can also be dried for further. Fresh or dried flowers can be prepared as teas, tinctures or in infused oil. 

The famous St John’s Wort oil can be used for healing skin conditions and to reduce pain and inflammation in the muscles and articulations - as in bruises, arthritis and even sciatica. To prepare the infused oil, gather the mature flowers around noon (after the morning dew has been evaporated) and place them in a clean, dry glass bottle (transparent). Cover the flowers with vegetable oil (almond, olive oil, sunflower oil, etc). Cover with a paper towel and a rubber band to avoid dust and insects from falling in. Leave it in a sunny window for 2 to 3 weeks, depending on how much sun you have. If you prefer to leave the oil under direct sunlight outside, even better. You must only care to bring the bottle every day to a sheltered place, where it can remain free from (condensed) moist or rain. You may keep adding new flowers to the oil every new harvest, so that the oil becomes more concentrated. When the oil gets a bright reddish color, it is ready to be used. Sieve the flowers with a clean cheese cloth into a dark glass bottle. Close the bottle tightly and label it with the date of bottling. Keep it in a cool, dark and dry place. 

In the links below you will find more practical information on identifying, harvesting and preparing St John's Wort. There is also a list of drug interactions that might occur with the regular use of SJW.

Table of SJW’s drug interactions

Hypericum - St Joan/John's Wort - with Susun Weed

St John's Wort - Hypericum perforatum - by HerbMentor