There is a large variation in the bioavailability of oral and intravenous Vitamin C. This is because the transporting capability of the intestinal sodium ascorbate co-transporter, SVCT1, a surface glycoprotein that facilitates Vitamin C absorption, 1 is limited and achieves maximal saturation around oral doses of 500-1000 mg. 2 Intravenous administration of Vitamin C bypasses the limitations of SVCT1-induced bioavailability.
In a dose concentration and pharmacokinetic modeling study of healthy hospitalized volunteers, consumption of 5-9 servings of fruits and vegetables daily resulted in steady state Vitamin C plasma concentrations of 80 µmol/L or less and peak values did not exceed 220 µmol/L even after maximum oral administration of 3 grams, six times daily. In this same study, at a dose of 100 grams, intravenous administration of Vitamin C achieved peak plasma concentrations as high as 15,000 µmol/L, a plasma concentration 70 times higher than oral administration. 3
ASCOR® is vitamin C indicated for the short term (up to 1 week) treatment of
scurvy in adult and pediatric patients age 5 months and older for whom oral
administration is not possible, insufficient or contraindicated.
Limitations of Use:
ASCOR® is not indicated for treatment of vitamin C deficiency that is not associated with signs and symptoms of scurvy.
Administration site reactions include pain and swelling.
ASCOR® should not be rapidly administered. Rapid intravenous administration (>250 mg/minute) of ASCOR® may cause temporary faintness or nausea, lethargy, flushing, dizziness, and headache.
Acute and chronic oxalate nephropathy have occurred with prolonged administration of high doses of ascorbic acid. ASCOR® is not indicated for prolonged administration. The maximum recommended duration is one week.
In patients with glucose-6-phosphate dehydrogenase deficiency severe hemolysis has occurred.
Ascorbic acid may interfere with laboratory tests based on oxidation-reduction reactions, including blood and urine glucose testing, nitrite and bilirubin levels, and leucocyte count testing. If possible, laboratory tests based on oxidation-reduction reactions should be delayed until 24 hours after infusion of ASCOR®.
Please see accompanying Full Prescribing Information for ASCOR®.
The information contained in this section of the site is intended for U.S. healthcare professionals only.