Hawthorn is a shrub whose fruits, flowers, and other parts have been long used as medicine for heart problems, high blood pressure, and high cholesterol. But more research is needed to know if it works.
Hawthorn usually doesn’t cause many side effects. Most common complaint is dizziness. You shouldn’t use hawthorn if you’re pregnant or breastfeeding, since little is known about its safety.
Hawthorn also may interfere with certain drugs and heighten their effect. Examples include medication for high blood pressure, and nitrates and digoxin.