Vitamin C - pure sodium ascorbate. 1/4 teaspoon = 1,000 mg. We recommend taking only 1/8 or 1/16 of a teaspoon at a time. This is very potent and if taken in excess can cause stomach upset and/or diarrhea. Vitamin C processes through the body in about 3 hours. Therefore, optimum dosage would be 1/8 or 1/16 of a teaspoon every 3 hours. Stomach tolerance can be increased slowly over time.