STUDY: Hawthorn: pharmacology and therapeutic uses.
JOURNAL: Am J Health Syst Pharm 2002 Mar 1;59(5):417-22
AUTHORS: Rigelsky JM, Sweet BV.
ABSTRACT: The uses, pharmacology, clinical efficacy, dosage and administration, adverse effects, and drug interactions of hawthorn are discussed. Hawthorn (Crataegus oxyacantha) is a fruit-bearing shrub with a long history as a medicinal substance. Uses have included the treatment of digestive ailments, dyspnea, kidney stones, and cardiovascular disorders. Today, hawthorn is used primarily for various cardiovascular conditions. The cardiovascular effects are believed to be the result of positive inotropic activity, ability to increase the integrity of the blood vessel wall and improve coronary blood flow, and positive effects on oxygen utilization. Flavonoids are postulated to account for these effects. Hawthorn has shown promise in the treatment of New York Heart Association (NYHA) functional class II congestive heart failure (CHF) in both uncontrolled and controlled clinical trials. There are also suggestions of a beneficial effect on blood lipids. Trials to establish an antiarrhythmic effect in humans have not been conducted. The limited data about hawthorn suggest that it may be useful in the treatment of NYHA functional class II CHF.
COMMENTARY: The recommended daily dose of hawthorn varies according to the preparation, since tinctures are typically stronger than teas, fluid extracts are stronger than tinctures and solid extracts are stronger than fluid extracts. It is a tradtional naturopathic remedy for cardiac weakness, though it does take some time for its effects to appear. It may we be especially useful for type A's since numerous studies link this blood group with cardiovascular disease over the other blood types.
At therapeutic dosages, hawthorn may cause a mild rash, headache, sweating, dizziness, palpitations, sleepiness, agitation, and gastrointestinal symptoms, although these are quite rare. There is some concern that hawthorn may interact with vasodilating medications and may potentiate or inhibit the actions of drugs used for heart failure, hypertension, angina, and arrhythmias, so check with your MD or naturopath before using hawthorn if you are on any heart medication.