Generic Name: Hawthorn

Tradition

Dosing

Adults (18 years and older):

For congestive heart failure, high-quality trials have used doses of 60 milligrams three times per day or 80 milligrams twice a day for products containing standardized extract WS 1442 (18.75% oligomeric procyanidines). The U.S. brand HeartCare® (Nature's Way) is standardized in this fashion.

Other high-quality trials have used doses of 100 milligrams three times per day, 200 milligrams twice a day, and up to 300 milligrams three times a day for products containing standardized extract LI 132 (2.2% flavonoids).

The dosage range recommended in review literature is 160-900 milligrams hawthorn extract per day in 2-3 divided doses (corresponding to 3.5-19.8 milligrams flavonoids or 30-168.8 milligrams oligomeric procyanidines). Some sources recommend a range of 240-480 milligrams per day for extracts standardized to 18.75% oligomeric procyanidines.

Children (younger than 18 years):

Not enough available scientific evidence.

Safety

Allergies:

Avoid if allergic to hawthorn or to members of the Crataegus genus. There is a case report of an immediate-type hypersensitivity reaction to hawthorn plants. It is not known if this applies to formulations taken by mouth.

Side Effects and Warnings:

There are limited reports of adverse effects associated with hawthorn. Numerous human trials, observational studies including over 4,500 patients, and case reports have noted rare adverse effects, including abdominal discomfort, nausea, agitation, dizziness, headache, fatigue, shortness of breath, skin rash, insomnia, sweating, and rapid heart rate.

Pregnancy and Breastfeeding:

Not recommended due to lack of sufficient data.

Interactions

Interactions with Drugs

Additive inotropic effects when used with cardiac glycoside drugs such as digoxin have been noted in animals without added toxicity. In humans, hawthorn has been used with the intention of decreasing digoxin doses, although data on safe and efficacious dosing in this setting is still limited.

Hawthorn may have additive activity with medications that lower blood pressure. Hawthorn may add to the activity of drugs that dilate blood vessels, and may decrease the effects of vasoconstrictors such as phenylephrine (Neo-Synephrine®), ephedrine or norepinephrine. Hawthorn may interact with cholesterol-lowering agents.

Interactions with Herbs and Dietary Supplements

Hawthorn may add to the effects on the heart of agents containing cardiac glycosides, such as foxglove (Digitalis purpurea).

Hawthorn may add to the effects of agents that lower blood pressure, and may also interact with agents that increase blood pressure.

Hawthorn may have additive activity with agents that reduce cholesterol levels such as garlic, niacin, or fish oil (omega-3 fatty acids).