St John’s Wort (Hypericum perforatum) is an ancient herb that was used extensively by the Greeks and the Romans, amongst other ancient civilizations. Today it is still used as a natural treatment for many conditions. However, overuse of St John’s Wort can cause some allergic reactions, so it is useful to understand what the plant is and what conditions you can safely use it for.
There are more than 160 species of St John’s Wort (source: Carrier Oils for Aromatherapy and Massage, Len Price) but it is the European native, Hypericum perforatum Linnnaeus, that is the most familiar plant for natural remedy uses. St John’s Wort is commonly found in France and the United Kingdom, although other genus are found throughout North America. It is a perennial plant that has yellow flowers with small black dots on the edges of the petals; this is where hypericin oil is found.
There are various stories as to how the plant attained its common English name, St John’s Wort; however, records do agree that the plant has been a valuable medicinal source for centuries. Dioscorides (40 – 90 AD), an ancient Greek physician, cited the use of the seeds and roots of St John’s Wort for several ailments, including one of its most popular uses, the treatment of depression (source: Ancient Herbs, Marina Heilmeyer). St John’s Wort was also used to treat arthritis, rheumatism and burns.
St John’s Wort was superstitiously used to keep away evil spirits and witches; in Medieval times, it was common for people to hang a sprig of St John’s Wort in their doorways and windows (source: Carrier Oils for Aromatherapy and Massage, Len Price). In addition, Medieval knights used St John’s Wort to heal sword wounds, due to the plant’s apparent bactericidal properties.
It is possible to extract both a carrier oil from the flowers of St John’s Wort and an essential oil from the leaves of St John’s Wort; however, only the carrier oil is commonly used in the practice of aromatherapy as the amount of essential oil that is produced is minimal. The carrier oil is deep red in color and, after extraction and processing, the result is a macerated oil that is used for aromatherapy practice; use St John’s Wort oil (as an oil applied externally) to treat:
(source: Carrier Oils for Aromatherapy and Massage, Len Price)
Use of St John’s Wort for Depression and Anxiety
St John’s Wort extracts are also a popular form of treatment for depression and anxiety; studies both in the United States and Europe suggest that St John’s Wort is an effective form of treatment for some cases of depression (source: Mayo Clinic: St John’s Wort Evidence and Carrier Oils for Aromatherapy and Massage, Len Price). However, further studies are ongoing as to how effective the herb is in treating more complex cases of anxiety and depression.
St John’s Wort carries certain cautions for use, depending on the format in which you take the herb. St John’s Wort macerated oil does not, in general, cause any known reactions, if used externally as a massage oil. However, ingestion of the herb may cause skin allergies, if you use it in large quantities for a prolonged period of time. It is not recommended to ingest St John’s Wort if you are pregnant or breastfeeding. Other side effects, such as headaches, dizziness, digestive disorders, fatigue and sensitivity to light may occur in a small percentage of those that take St John’s Wort extracts (source: Mayo Clinic: St John’s Wort: Safety).