Interactions
St. John's wort has the ability to interact with plants,
animals, and humans, in very different ways. The reason this
plant has the ability to interact is because of the chemicals
found in the leaves and the oil secreted from the flower. The
chemical found in the plant is called hypercin. When this
chemical comes in contact with other plants it has the ability
to control their nutrient intake. This coupled with the plants
powerful root system allows the plant to limit the native
plant's availability for water and nutrients, causing the plant
to die.
Hypericum perforatum has an equally depressing effect on most animals. The chemicals in the leaves are toxic to most of the animals it comes in contact with. The chemicals work to depress the animal's central nervous system. The animal will experience sensitivity to light and will lose weight rapidly. This is a very difficult issue to manage since the smallest amount of sunlight can have a great effect on the animal. Most commonly the animal will die of dehydration. Animals such as cattle, white tailed deer, and sheep are affected the most. However, goats which often come in contact with the plant have never experienced these side effects.
There are many herbs that have medicinal purposes such as Tea plants and Hemp. St. John's wort is also very useful to humans, because of it's various medicinal purposes, and is now available over the counter. Hypericum perforatum is most commonly used for mild to moderate depression and anxiety. The hypercin has been shown to increase the level of serotonin, a chemical that affects emotions, in the brain. Recent studies do not suggest using the herb when treating severe depression. This is because hypercin works like most antidepressants, blocking certain chemicals from the brain, but less harshly. Studies have also shown that St. John's wort works particularly well on children partially because of the lower amount of side effects.
St. John's wort serves various other medicinal purposes that have been less documented in recent years. For instance, lotions containing hypercin have been found to reduce the appearance of scars, such as those from Cesarean sections. It is also used to reduce the effects of premenstrual syndrome. Recent reports show that symptoms of PMS were reduced by more than half in most women. St. John's wort also has the ability to increase the activity of various enzymes in the liver, breaking down more toxins. However, these breakdowns have the ability to interact with other drugs making them less effective.