AMERICAN HEALTH 1x 90 CAP ESTER-C 1000 CITRUS BIOFLAVONOIDS. Non-acidic Ester-C is a breakthrough patented formula that contains naturally-occurring Vitamin C metabolites and is quickly absorbed. Its unique manufacturing process neutralizes pH making it gentle on the digestive system.:. (Note: This product description is informational only. Always check the actual product label in your possession for the most accurate ingredient information before use. For any health or dietary related matter always consult your doctor before use.)