This information describes the common uses of Hawthorn, how it works, and its possible side effects.

Common Name

May flower, Shan Zha, Crataegus berries, Quickthorn, Whitehorn

How It Works

Hawthorn may be helpful in some patients with heart failure. Definitive data are needed on safety and efficacy.

Derived from the flower, leaves, and fruits of the plant, hawthorn is also known in Asia as Shan Zha. It is used in traditional Chinese medicine to improve digestion and treat heart problems. Hawthorn also has a long history in European medicine as a heart tonic.

Studies in the lab suggest a range of anti-inflammation, heart-protective, and digestion-improving properties. Studies in humans show benefits in patients with congestive heart failure, although a few trials did not.

More studies are needed to confirm safety and effectiveness of hawthorn. In addition, it should not be used in place of conventional heart failure therapies and its use should be monitored by the treating physician.

Purported Uses

  • To improve digestion
    Hawthorn is used to relieve indigestion in traditional Chinese medicine, but clinical studies are lacking.
  • To treat heart disease
    In some studies, hawthorn extract used as add-on therapy was found to be beneficial in heart failure patients. More definitive data are needed.
  • To lower high blood pressure
    Data are conflicting. More research is needed.

Do Not Take If

  • You are pregnant.
  • You are taking antiplatelets or anticoagulants: A lab study suggests hawthorn may increase the side effects of these drugs. Although clinical relevance has yet to be determined, patients taking heart failure medications should only use hawthorn under direction and monitoring by the treating physician.
  • You are taking digoxin: Lab studies suggest hawthorn may interfere with some heart medications like digoxin. Therefore, any use of this supplement should be discussed with, and monitored by, your treating physician.

Side Effects

  • Generally well tolerated
  • Most common: Dizziness
  • Infrequent or mild: Nausea, cardiac and gastrointestinal complaints
  • Overdose: Low blood pressure, irregular heart beat

Special Point

Hawthorn should not be used in place of proven conventional therapies for heart failure, and its use should be monitored by the treating physician.