Side Effects and Cautions

• Thunder god vine can cause severe side effects and can be poisonous if it is not carefully extracted from the skinned root. Other parts of the plant-including the leaves, flowers, and skin of the root-are highly poisonous and can cause death.
• The extract of thunder god vine used in the NIAMS study was well tolerated. However, thunder god vine can cause diarrhea, upset stomach, hair loss, headache, menstrual changes, and skin rash.
• Thunder god vine has been found to decrease bone mineral density in women who take the herb for 5 years or longer. This side effect may be of particular concern to women who have osteoporosis or are at risk for the condition.
• Thunder god vine decreases sperm count and so may be associated with male infertility.
• Tell your health care providers about any complementary and alternative practices you use. Give them a full picture of what you do to manage your health. This will help ensure coordinated and safe care.