Chest pain or discomfort in the chest can occur when the heart is not pumping enough blood, thus depriving the heart muscle of oxygen. The condition is called angina pectoris. When the same symptoms occur at rest or become severe, unstable angina is the diagnosis. Unstable angina is treated as an emergency. In China, doctors have been using an injection of the herbal extract, puerarin, as a treatment for heart disease and for unstable angina. Puerarin is extracted from the herb, puerariae lobata, which is also known as kudzu or by its Chinese name, Gegen.
The authors of this review found 20 trials, which altogether involved 1240 people with unstable angina. However, the authors could not come to a firm conclusion about the effectiveness of puerarin injections because these studies were of poor quality. Nor could the authors be sure that puerarin injections are safe because of inadequate reporting of adverse reactions from the 20 trials. What is needed is a large clinical trial in which people with unstable angina are randomly assigned to receive either a puerarin injection (plus standard treatment) or a standard treatment. The participants should be followed long enough to determine whether this treatment actually saves lives. Until such well-designed trials are published, it will not be known whether puerarin injection benefits people with unstable angina.