As the number of individuals, particularly the elderly, using herbal products with prescription drugs continues to grow, the risk for adverse interactions increases but remains poorly recognized. The true incidence and nature of adverse herb reactions or herb-drug interactions remains unknown since no postmarketing surveillance mechanism exists. Adverse events are greatly underreported, and information regarding safety mainly comes from case reports and suboptimally conducted studies in a limited number of healthy young volunteers or patients with limited comorbidities. Therefore, convincing evidence for the safety of herbal products in the elderly is lacking, and the true magnitude of problems that herb-drug interactions pose to public health, particularly in elderly patients with cardiovascular diseases, is not known. Since cardiovascular diseases themselves are life threatening, necessitate use of multiple medications and occur in a population with extensive comorbidities, the risk of herb-drug and herb-disease interactions is not minor and cannot be ignored. This review addresses these concerns in an effort to raise awareness about the use of herbal medicine by the elderly and its potential adverse impact on the efficacy of prescription medications that can increase predisposition to catastrophic events such as major bleeding, inadequate anticoagulation leading to undesired clotting, transplant organ rejection and life-threatening cardiac arrhythmias.