Oral administration of large doses of ascorbic acid may cause mild gastrointestinal disturbances, especially in individuals with a history of gastrointestinal disorders. In cases where either high doses of Vitamin C are necessary, or Vitamin C is administered to individuals with a personal history of gastrointestinal disorders, we recommend the administration of Gentle Vitamin C. This product provides vitamin C in the form of calcium ascorbate, a non-acidic and fully absorbable form of Vitamin C, the intake of which is recommended for people with a history of gastrointestinal disorders. Up to 3g of Vitamin C can be taken daily using this product (6 tablets). In these cases we recommend taking the required tablets throughout the day. Each tablet also provides 77mg of calcium, which can contribute significantly to your daily calcium intake, especially when taking a large number of tablets daily. PRECAUTIONS & SIDE EFFECTS Allergies: None. Precautions: Intake of more than 1000mg of Vitamin C daily may cause mild gastrointestinal upset.