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Ascorbic Acid

Medically reviewed by Drugs.com. Last updated on Mar 25, 2019.

Pronunciation

(a SKOR bik AS id)

Index Terms

  • Ascorbate Sodium
  • Ascorbic Acid/Ascorbate Sodium
  • Sodium Ascorbate
  • Vitamin C

Dosage Forms

Excipient information presented when available (limited, particularly for generics); consult specific product labeling. [DSC] = Discontinued product

Capsule Extended Release, Oral:

C-Time: 500 mg

Generic: 500 mg

Capsule Extended Release, Oral [preservative free]:

Generic: 500 mg

Crystals, Oral:

Vita-C: (120 g, 480 g) [animal products free, gelatin free, gluten free, lactose free, no artificial color(s), no artificial flavor(s), starch free, sugar free, yeast free]

Liquid, Oral:

BProtected Vitamin C: 500 mg/5 mL (236 mL) [contains propylene glycol, saccharin sodium, sodium benzoate; citrus flavor]

Generic: 500 mg/5 mL (118 mL, 473 mL)

Packet, Oral:

Generic: 500 mg (80 ea)

Powder, Oral:

Ascocid: (227 g)

Generic: (113 g, 120 g, 480 g)

Powder Effervescent, Oral:

Ascocid-ISO-pH: (150 g) [corn free, rye free, wheat free]

Solution, Injection:

Generic: 500 mg/mL (50 mL)

Solution, Injection [preservative free]:

Mega-C/A Plus: 500 mg/mL (50 mL [DSC])

Generic: 500 mg/mL (50 mL)

Solution, Intravenous [preservative free]:

Ascor: 500 mg/mL (50 mL) [contains edetate disodium]

Solution, Injection, as sodium ascorbate [preservative free]:

Ortho-CS 250: 250 mg/mL (100 mL [DSC]) [contains edetate disodium, water, sterile]

Generic: 250 mg/mL (30 mL [DSC])

Syrup, Oral:

Generic: 500 mg/5 mL (118 mL [DSC])

Tablet, Oral:

Asco-Tabs-1000: 1000 mg [color free, starch free, sugar free]

Generic: 100 mg, 250 mg, 500 mg, 1000 mg

Tablet, Oral [preservative free]:

Generic: 250 mg, 500 mg

Tablet Chewable, Oral:

Chew-C: 500 mg

Fruit C 500: 500 mg [animal products free, gelatin free, gluten free, kosher certified, lactose free, no artificial color(s), no artificial flavor(s), starch free, sugar free, yeast free]

Fruit C: 100 mg [animal products free, gelatin free, gluten free, lactose free, no artificial color(s), no artificial flavor(s), starch free, sugar free, yeast free]

Fruity C: 250 mg

VitaChew Vit C Citrus Burst: 125 mg

Generic: 100 mg, 250 mg, 500 mg

Tablet Chewable, Oral [preservative free]:

C-500: 500 mg [animal products free, gluten free, soy free, starch free, yeast free]

Generic: 500 mg

Tablet Extended Release, Oral:

Cemill: 500 mg

Cemill SR: 1000 mg

Generic: 500 mg, 1000 mg [DSC], 1500 mg

Wafer, Oral [preservative free]:

Acerola C 500: 500 mg (50 ea) [corn free, no artificial color(s), no artificial flavor(s), wheat free, yeast free; contains acerola (malpighia glabra)]

Brand Names: U.S.

  • Acerola C 500 [OTC]
  • Asco-Tabs-1000 [OTC]
  • Ascocid [OTC]
  • Ascocid-ISO-pH [OTC]
  • Ascor
  • BProtected Vitamin C [OTC]
  • C-500 [OTC]
  • C-Time [OTC]
  • Cemill SR [OTC]
  • Cemill [OTC]
  • Chew-C [OTC]
  • Fruit C 500 [OTC]
  • Fruit C [OTC]
  • Fruity C [OTC]
  • Mega-C/A Plus [DSC]
  • Ortho-CS 250 [DSC]
  • Vita-C [OTC]
  • VitaChew Vit C Citrus Burst [OTC]

Pharmacologic Category

  • Vitamin, Water Soluble

Pharmacology

Ascorbic acid is an essential water soluble vitamin that acts as a cofactor and antioxidant. Ascorbic acid is an electron donor used for collagen hydroxylation, carnitine biosynthesis, and hormone/amino acid biosynthesis. It is required for connective tissue synthesis as well as iron absorption and storage (IOM 2000).

Absorption

Oral: Readily absorbed in the intestine; an active process thought to be saturable and dose dependent (30 to 180 mg/day: 70% to 90%; >1,000 mg/day: ≤50%) (IOM 2000)

Distribution

Pituitary and adrenal glands, leukocytes, eye tissues and humors, and brain; lower concentrations in the plasma and saliva (IOM 2000)

Metabolism

Reversibly oxidized to dehydroascorbic acid (DHA); both ascorbic acid and DHA are active. Unabsorbed ascorbic acid is degraded in the intestine (IOM 2000)

Excretion

Urine (with high serum concentrations) (IOM 2000); there is an individual specific renal threshold for ascorbic acid; when blood levels are high, ascorbic acid is excreted in urine, whereas when the levels are subthreshold (doses up to 80 mg/day) very little if any ascorbic acid is excreted into urine

Onset of Action

Reversal of scurvy symptoms: 2 days to 3 weeks

Half-Life Elimination

10 hours (Schwedhelm 2003). Biological half-life: 8 to 40 days (IOM 2000)

Protein Binding

25%

Use: Labeled Indications

Ascorbic acid deficiency: Treatment of symptoms of mild deficiency; use in conditions requiring an increased intake (eg, burns, wound healing)

Dietary supplement: As a dietary vitamin C supplement

Scurvy: Prevention and treatment of scurvy

Off Label Uses

Severe sepsis or septic shock

Data from one small, retrospective, before-after study suggest that IV ascorbic acid (vitamin C) in combination with IV hydrocortisone and IV thiamine in patients with severe sepsis or septic shock may be effective in decreasing mortality and preventing organ dysfunction (Marik 2017). There are ongoing studies to confirm these findings in a larger population with a more robust study design.

Contraindications

There are no contraindications listed in the manufacturer's labeling.

Dosing: Adult

Ascorbic acid deficiency: IM, IV, SubQ: 70 to 150 mg daily is an average protective dose; doses 3 to 5 times the RDA may be adequate for conditions with increased requirements.

Burns: IM, IV, SubQ: 1 to 2 g daily for severe burns; dose may be determined by extent of tissue injury

Parenteral nutrition, maintenance requirement: IV: 200 mg/day (ASPEN [Vanek 2012]).

Scurvy:

IM, IV, SubQ: 300 to 1,000 mg daily; dose and duration of therapy should be individualized; doses up to 6 g per day have been administered (per manufacturer).

Ascor: IV: 200 mg once daily for up to a maximum of 7 days. If no improvement after one week of treatment, retreat until resolution of symptoms is observed.

Oral: 100 to 300 mg daily until body stores are replenished; dose and duration of therapy should be individualized; doses as low as 10 mg may be effective (Hirschmann 1999; Popovich 2009; Weinstein 2001).

Severe sepsis or septic shock (off-label use): IV: 1.5 g over 30 to 60 minutes; repeat every 6 hours for 4 days or until ICU discharge; administer in combination with IV thiamine and IV hydrocortisone (Marik 2017).

Wound healing: IM, IV, SubQ: 300 to 500 mg daily for 7 to 10 days pre- and post-operatively; larger doses have also been used

Dosing: Geriatric

Refer to adult dosing.

Dosing: Pediatric

Parenteral nutrition additive, maintenance requirement (ASPEN [Vanek 2012]; ESPGHAN/ESPEN/ESPR/CSPEN [Bronsky 2018]):

Infants: IV: 15 to 25 mg/kg/day; maximum daily dose: 80 mg/day

Children and Adolescents: IV: 80 mg daily

Scurvy, treatment:

Infants, Children, and Adolescents: Limited data available: Oral, IM, IV: Initial: 100 to 300 mg/day in divided doses for 1 week followed by 100 mg/day until normalization of tissue saturation (~1 to 3 months) (Kleinman 2013; Kliegman 2016; Popovich 2009; Weinstein 2001)

Manufacturer's labeling: Ascor:

Infants ≥5 months: IV: 50 mg once daily for 1 week

Children <11 years: IV: 100 mg once daily for 1 week

Children ≥11 years and Adolescents: IV: 200 mg once daily for 1 week

Reconstitution

Prior to IV administration, dilute in a large volume parenteral solution (eg, D5W, SWFI). Refer to manufacturer's labeling for additional preparation instructions. Note: Pressure may develop in the vial during storage.

Administration

Oral administration is preferred unless malabsorption is suspected. IM administration is preferred when the parenteral route is required. Oral products may be administered with food.

Injection: For IM (preferred), IV, or SubQ administration. Avoid rapid IV injection; may cause temporary faintness or dizziness.

Ascor: For IV use only. Following dilution in an appropriate IV solution (eg, D5W, SWFI), administer by slow IV infusion at a rate of 33 mg/minute.

Dietary Considerations

Some products may contain sodium.

High dietary sources of ascorbic acid are citrus fruit, tomatoes/tomato juice, and potatoes; also found in other fruits, broccoli, cabbage, cauliflower, spinach, and strawberries. Absorption from diet and supplements is similar (IOM 2000).

Dietary recommended adequate intake (AI) (IOM 2000):

0 to 6 months: 40 mg daily

7 to 12 months: 50 mg daily

Dietary recommended daily allowance (RDA) (IOM 2000): Note: Patients with hemochromatosis, G6PD deficiency, and renal impairment may be at increased risk for adverse effects when exceeding recommended intake limits.

1 to 3 years: 15 mg daily; upper limit of intake should not exceed 400 mg daily

4 to 8 years: 25 mg daily; upper limit of intake should not exceed 650 mg daily

9 to 13 years: 45 mg daily; upper limit of intake should not exceed 1,200 mg daily

14 to 18 years: Upper limit of intake should not exceed 1,800 mg daily

Males: 75 mg daily

Females: 65 mg daily

Pregnant females: 80 mg daily; upper limit of intake should not exceed 1,800 mg daily

Lactating females: 115 mg daily; upper limit of intake should not exceed 1,800 mg daily

>18 years: Upper limit should not exceed 2,000 mg daily

Males: 90 mg daily

Females: 75 mg daily

Pregnant females: 19 to 50 years: 85 mg daily

Lactating females: 19 to 50 years: 120 mg daily

Adult smoker: Add an additional 35 mg daily

Storage

Injection: Store under refrigeration at 2°C to 8°C (36° to 46°F); protect from light. Use within 4 hours of vial entry; discard remaining portion.

Oral: Store at room temperature.

Drug Interactions

Aluminum Hydroxide: Ascorbic Acid may increase the absorption of Aluminum Hydroxide. Consider therapy modification

Amphetamines: Ascorbic Acid may decrease the serum concentration of Amphetamines. Monitor therapy

Bortezomib: Ascorbic Acid may diminish the therapeutic effect of Bortezomib. Management: Patients should avoid taking vitamin C supplements and vitamin C-containing multivitamins during their bortezomib therapy. It is probably unnecessary to advise patients to avoid foods/beverages that contain vitamin C (e.g., citrus fruits, etc.). Consider therapy modification

Copper: May decrease the serum concentration of Ascorbic Acid. Management: To minimize the risk for ascorbic acid degradation, add multivitamin product to TPN solution immediately prior to infusion or administer multivitamin and copper in separate containers. Consider therapy modification

CycloSPORINE (Systemic): Ascorbic Acid may decrease the serum concentration of CycloSPORINE (Systemic). Monitor therapy

Deferoxamine: Ascorbic Acid may enhance the adverse/toxic effect of Deferoxamine. Left ventricular dysfunction is of particular concern. Management: Avoid ascorbic acid doses greater than 200 mg/day. Lower doses may be given to patients without cardiac failure, after one month of regular treatment with deferoxamine alone, ideally soon after setting up the infusion pump. Monitor cardiac function. Consider therapy modification

Estrogen Derivatives: Ascorbic Acid may increase the serum concentration of Estrogen Derivatives. Monitor therapy

Test Interactions

False-negative stool occult blood 48 to 72 hours after ascorbic acid ingestion.

May interfere with laboratory tests based on oxidation-reduction reactions (eg, blood and urine glucose testing, nitrite and bilirubin levels, leucocyte count). If possible, laboratory tests based on oxidation-reduction reactions should be delayed until 24 hours after dose.

Adverse Reactions

1% to 10%: Endocrine & metabolic: Hyperoxaluria (with large doses)

<1%: Diarrhea, dizziness, fatigue, flank pain, flushing, headache, heartburn, nausea, vomiting

Warnings/Precautions

Concerns related to adverse effects:

• Oxalate nephropathy/nephrolithiasis: Acidification of the urine by ascorbic acid may cause precipitation of cysteine, urate or oxalate stones. Acute and chronic oxalate nephropathy has been reported with prolonged administration of high IV doses. Patients with renal disease including renal impairment, history of oxalate kidney stones, elderly patients and pediatric patients <2 years of age may be at increased risk. Monitor renal function in patients at increased risk. Discontinue in patients who develop oxalate nephropathy.

Disease-related concerns:

• Diabetes: Patients with diabetes mellitus should not take excessive doses for extended periods of time.

• Glucose-6-phosphatase dehydrogenase deficiency: Hemolysis has been reported in patients with glucose-6-phosphatase dehydrogenase (G6PD) deficiency and the risk for severe hemolysis may be increased during ascorbic acid therapy. Dose reductions may be necessary along with appropriate monitoring (eg, hemoglobin, blood counts). Discontinue treatment if hemolysis is suspected.

• Hemochromatosis: Use with caution in patients with hemochromatosis; excess ascorbic acid intake may increase the risk of adverse events (IOM 2000).

• Renal impairment: Use with caution in patients with renal impairment or patients prone to recurrent renal calculi; may have increased risk of developing acute or chronic oxalate nephropathy.

Special populations:

• Elderly: Use with caution in the elderly; may be at increased risk for oxalate nephropathy.

• Pediatric: Use with caution in the children <2 years of age; may be at increased risk for oxalate nephropathy due to immature kidney function.

Dosage form specific issues:

• Aluminum: The parenteral product may contain aluminum; toxic aluminum concentrations may be seen with high doses, prolonged use, or renal dysfunction. Premature neonates are at higher risk due to immature renal function and aluminum intake from other parenteral sources. Parenteral aluminum exposure of >4 to 5 mcg/kg/day is associated with CNS and bone toxicity; tissue loading may occur at lower doses (Federal Register 2002). See manufacturer's labeling.

• Benzyl alcohol and derivatives: Some dosage forms may contain sodium benzoate/benzoic acid; benzoic acid (benzoate) is a metabolite of benzyl alcohol; large amounts of benzyl alcohol (≥99 mg/kg/day) have been associated with a potentially fatal toxicity (“gasping syndrome”) in neonates; the “gasping syndrome” consists of metabolic acidosis, respiratory distress, gasping respirations, CNS dysfunction (including convulsions, intracranial hemorrhage), hypotension, and cardiovascular collapse (AAP ["Inactive" 1997]; CDC 1982); some data suggests that benzoate displaces bilirubin from protein binding sites (Ahlfors 2001); avoid or use dosage forms containing benzyl alcohol derivative with caution in neonates. See manufacturer's labeling.

• Injection: Avoid rapid IV injection; may cause temporary faintness or dizziness.

• Sodium: Some products may contain sodium; use with caution in sodium restricted patients.

Monitoring Parameters

Renal function (patients at risk for developing oxalate nephropathy/nephrolithiasis); hemoglobin and blood counts (patients with G6PD deficiency).

Pregnancy Risk Factor

C

Pregnancy Considerations

Animal reproduction studies have not been conducted. Maternal plasma concentrations of ascorbic acid decrease as pregnancy progresses due to hemodilution and increased transfer to the fetus. Some pregnant women (eg, smokers) may require supplementation greater than the RDA (IOM 2000).

Patient Education

• Discuss specific use of drug and side effects with patient as it relates to treatment. (HCAHPS: During this hospital stay, were you given any medicine that you had not taken before? Before giving you any new medicine, how often did hospital staff tell you what the medicine was for? How often did hospital staff describe possible side effects in a way you could understand?)

• Patient may experience diarrhea, nausea, vomiting, or injection site irritation. Have patient report immediately to prescriber signs of kidney problems (urinary retention, hematuria, change in amount of urine passed, or weight gain), signs of a kidney stone (back pain, abdominal pain, or hematuria), severe loss of strength and energy, dark urine, or jaundice (HCAHPS).

• Educate patient about signs of a significant reaction (eg, wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat). Note: This is not a comprehensive list of all side effects. Patient should consult prescriber for additional questions.

Intended Use and Disclaimer: Should not be printed and given to patients. This information is intended to serve as a concise initial reference for health care professionals to use when discussing medications with a patient. You must ultimately rely on your own discretion, experience, and judgment in diagnosing, treating, and advising patients.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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