Mistletoe is culturally associated with Christmas tradition but as a plant, it is found worldwide and there are more than a thousand species in existence. It grows on every continent except Antarctica.
The mistletoe found in Europe is generally of the genus Viscum album while the North American mistletoe is of the genus Phoradendron. There are a couple of Phoradendron species in the U.S. and they are usually characterized by oval green leaves and small white berries.
In Kentucky, mistletoe (Phoradendron serotinum) is considered to be native to the state. It is the only mistletoe species in Kentucky.
The leaves, stems, and berries of the mistletoe plant can be toxic when ingested. The plant contains Phoratoxin and Viscotoxin which are poisonous proteins. Toxic effects include digestion problems, collapse, drowsiness, and hypotension.
The good news is that Kentucky mistletoe is less toxic than its European counterpart. In cases of accidental exposure to mistletoe, most people did not suffer from any side effects. Only a few have experienced gastrointestinal upset.
European mistletoe (Viscum album) is quite different from American mistletoe. While American mistletoe has been used as a holiday decoration, European mistletoe has been used in traditional medicine to aid in cancer treatment and symptoms of menopause, headaches, and seizures. It is also more toxic than American mistletoe.
During the holiday season, it is important to avoid exposure to mistletoe. Most human exposure is in the form of mistletoe berries eaten by children or brewed into tea.
No antidote is currently available to relieve any symptoms from mistletoe ingestion.