This plant has been used as an herbal remedy for its anti-inflammatory and healing properties since the Middle Ages. Many ancient herbalists, including Hippocrates and Pliny, recorded the medicinal properties of St. John's wort. It was noted for its wound-healing and diuretic properties as well as for the treatment of back pain. In 1633, Gerard's Herbal recorded the plant's use as a balm for burns. The oil of the plant also was popular during this time. An olive oil extract of the fresh flowers that acquires a reddish color has been taken internally for the treatment of anxiety, but also has been applied externally to relieve inflammation and promote healing. Its topical application is believed to be particularly useful in the management of hemorrhoids.