Finally, hawthorn sometimes lowers blood pressure a little, but seldom enough to make a significant difference. It may be helpful for other heart-related conditions, such as angina and atherosclerosis in general, but there is as yet little direct evidence. There has been a significant amount of solid research regarding the use of hawthorn as a treatment for congestive heart failure. The cumulative results strongly suggest that hawthorn is an effective treatment for congestive heart failure. Comparative studies suggest that hawthorn is about as effective as a low dose of the conventional drug captopril, although whether it produces the same long-term benefits as captopril is unknown.
Full effects appear to take several weeks or months to develop.
Safety Issues Hawthorn appears to be safe. Germany's Commission E lists no known risks, contraindications, or drug interactions with hawthorn, and mice and rats have been given phenomenal doses without showing significant toxicity. However, since hawthorn affects the heart, it shouldn't be combined with other heart drugs without a doctor's supervision. People with especially low blood pressure should also exercise caution. Safety in young children, pregnant or nursing women, or those with severe liver, heart, or kidney disease has not been established.