Comfrey, otherwise known as blackwort and slippery root, is used topically for wounds, scratches, sunburn, and skin irritations. It is brewed into a tea and used for cough, diarrhea, and heavy menstrual periods. Unfortunately, comfrey also contains pyrrolizidine alkaloids, which are highly toxic to the liver. Symptoms of toxicity include stomach pain, water retention, nausea, and jaundice.
Germander is a plant in the mint family that has been brewed into tea for the management of weight, gallbladder disease, and mild diarrhea. Several countries have banned the use of germander due to side effects such as liver toxicity and death. Signs of liver toxicity are yellowing of the skin, yellowing of the eyes, itching, abdominal pain, nausea, vomiting, and dark urine.
Lobelia inflata is also known as Indian tobacco. It is used to improve respiration through relaxation of the bronchial tubes and the breakup of mucus in the respiratory tract. Lobelia can be applied topically or added to a warm bath to relax the muscles. Some claim it can be effective in seizure prevention. However, the use of lobelia does not come without risks. High doses can cause nausea, vomiting, diarrhea, convulsions, rapid heartbeat, coma, and even death.