Herbal medicine refers to using plants for medicinal purposes and has a long tradition outside of conventional medicine. Plants have been used medicinally for thousands of years by early Chinese, Egyptians, and other ancient cultures. While chemical analysis and modified plant extracts became popular in the 19th century, herbal medicine use has increased in recent decades due to a public interest in natural remedies and the high cost of prescription drugs. Approximately 25% of modern drugs are still derived from or mimic natural plant compounds, and herbal medicine continues to be widely used globally for primary healthcare.