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 procyanidins). 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 procyanidins). Some sources recommend a range of 240-480 milligrams per day for extracts standardized to 18.75% oligomeric procyanidins.