PDR for Herbal Medicines

272 /ENGLISH HAWTHORN

.=- Habitat: The plant is indigenous to northern temperate zones

of Europe, Asia, and North America.

Production: Hawthorn consists of the leaves and flowers of

Crataegus laevigata and. occasionally other species. The

medicinal parts of the Hawthorn plant are collected in the

wild and dried at room temperature.

Not to be Confused With: Hawthorn is sometimes mistaken

for the flowers, leaves, and fruit of Robinia pseudoacacia,

Sorbus aucuparia or Prunus spinosa.

Other Names: Haw, May, Whitethorn, Hawthorn

ACTIONS AND PHARMACOLOGY

COMPOUNDS

Flavonoides (1.8%): O-glycosides, including hyperoside

(0.28%), rutin (0.17%)

6-C- and 8-C-glycosyl compounds, including vitexin

(0.02%), vicenin-1, orientin

6-C- and 8-C-glycosyl compounds, linked O-glycosidically

as well as with other monosaccharides, including vitexin-2"-

O-alpha-L-rhamnoside (0.53%), vitexin-2"-0-alpha-L-

rhamnoside-4'"-acetate

Oligomeric proanthocyanidins (2.4%)

Biogenic amines, including tyramine

Triterpenes ( 0.6%): including oleanolic acid, ursolic acid, 2-

alpha-hydroxy oleanolic acid (crataegolic acid)

EFFECTS

The active principles are procyanidins and flavonoids. They

cause an increase in coronary blood flow due to dilatory

effects resulting in an improvement of myocardial blood

flow. The drug is positively inotropic and positively chrono-

tropic. The cardiotropic effect of Crataegus is said to be

caused by the increased membrane permeability for calcium

as well as the inhibition of phosphodiesterase with an

increase of intracellular cylco-AMP concentrations. In-

creased coronary and myocardial circulatory perfusion and

reduction in peripheral vascular resistance were observed.

High doses may cause sedation. This effect has been

attributed to the oligomeric procyanidins (Anonym, 1994).

Crataegus extract has been found to prolong the refractory
period and increase the action potential duration in guinea
pig papillary muscle. One study demonstrated that a Cra-
taegus extract blocked the repolarizing potassium currents in
ventricular myocytes of guinea pigs. This effect is similar to
that of class HI antiarrhythmic drugs and may explain the
antiarrhythmic effect of Hawmorn (Muller, 1999).

PDR FOR HERBAL MEDICINES

INDICATIONS AND USAGE

Approved by Commission E:

• Decrease in cardiac output (Stage II NYHA)

Hawthorn is used for senile heart, chronic cor pulmonale,

and mild forms of bradycardia! arrhythmias.

Unproven Uses: In folk medicine, Hawthorn is also used as a

cardiotonic, for hypertension, ischemia of the heart, arrhyth-

mia and as a sedative. Hawthorn has a high flavonoid content

and is used to prevent collagen destruction in joints and

decrease inflammation and decrease the fragility of capillar-

ies. Hawthorn has shown some effectiveness in lowering

cholesterol levels in at least one study. Several extracts from

different componants of the plant have demonstrated antioxi-

dant effects.

Chinese Medicine: In China, Hawthorn is used to reduce

food stagnancy and blood stasis (Chen, 1995).

Homeopathic Uses: Therapeutic dilutions are used for

cardiac insufficiency, senile cardiac insufficiency, dysrhyth-

mia, and angina pectoris.

CLINICAL STUDIES

Cardiac Effects

Several studies that have used animal models demonstrate

the cardiac effects of Hawthorn. The influence of the main

flavonoids from Hawthorn on coronary flow, heart rate, left

ventricular pressure and the velocity of contraction and

relaxation was investigated on isolated guinea pig hearts

maintained at a constant perfusion pressure was the focus of

one study. The study recorded an increase in coronary flow

of 186% for one of the main glycosides, luteolin-7-gluco-

side; 66% for the hyperoside component and 66% for the

rutin flavonoid. Coronary relaxation velocity increased by

104% in the luteolin-7-glucoside arm, 62% for hyperoside

and 73% for rutin. Positive inotropic and chronotropic

effects were noted for all of the above extracts as well. The

beta adrenergic effects of the flavonoids were prevented by

the addition of propranolol. The authors postulate that the

mechanism of action for the cardiac effects of Hawthorne is

due to the inhibition of the 3', 5'-cyclic adenosine mono-

phosphate phosphodiesterase enzyme (Schussler, 1995). It

should be noted that in a more recent study, the positive

inotropic effect of Hawthorn was not attributed to phospho-

diesterase inhibition or to a beta-sympathomimetic effect

(Muller, 1999).

Another small, placebo controlled, randomized double-blind

study was performed to test the efficacy of a special extract

(WS 1442) of Hawthorn in a group of 30 patients with stage

II NYHA cardiac insufficiency. Treatment duration was 8

weeks. Primary parameters were alteration in the pressure-x-