Usage
Calcium ascorbate is primarily prescribed for the prevention and treatment of Vitamin C deficiency (hypovitaminosis C), particularly scurvy. It can also be used as a calcium supplement and is sometimes used in patients receiving deferoxamine to promote iron excretion. Its pharmacological classification is as a vitamin supplement and antioxidant. Its mechanism of action involves acting as a cofactor in various enzymatic reactions, including collagen synthesis, carnitine biosynthesis, and tyrosine metabolism. It also plays a crucial role as an antioxidant, scavenging free radicals and protecting cells from oxidative damage.
Alternate Names
Calcium ascorbate is also known as calcium diascorbate, and is sometimes referred to simply as Vitamin C, although technically this is a broader term. Brand names include many formulations under names like Ester-C and Cenolate. It can be available as part of many multivitamins, often without any distinguishing name beyond Calcium ascorbate or ascorbate calcium.
How It Works
Pharmacodynamics: Calcium ascorbate exerts its effects by participating in numerous physiological processes. As a cofactor for various enzymes, it is essential for collagen synthesis, crucial for wound healing, bone health, and maintaining the integrity of blood vessels. It contributes to immune function by enhancing the activity of phagocytes and supporting antibody production. As an antioxidant, it neutralizes free radicals, protecting cells from oxidative stress. Its ability to enhance iron absorption makes it beneficial in preventing iron deficiency anemia.
Pharmacokinetics: Calcium ascorbate is readily absorbed from the gastrointestinal tract, although absorption may be reduced at high doses. It is widely distributed throughout the body’s tissues. The liver metabolizes ascorbate primarily through oxidation and sulfation. Excess ascorbate is excreted renally. The half-life of ascorbate varies depending on the dosage and can range from several hours to several days.
Dosage
Standard Dosage
Adults:
The recommended daily allowance (RDA) for adult men is 90 mg/day and for adult women, 75 mg/day. Therapeutic doses for treating scurvy are typically higher, around 500 mg/day. For general supplementation or preventing deficiency, dosage can range from 500 mg to 2 grams daily divided into one or two doses. Some studies investigating immune support have used up to 2000 mg daily.
Children:
The RDA for children varies by age. Doses for treating scurvy are usually between 100-300 mg/day, given for at least 2 weeks. General guidelines for children are:
- Children 1-3 years of age: 15 mg/day
- Children 4-8 years of age: 25 mg/day
- Children 9-13 years of age: 45 mg/day
- Teenagers 14-18 years of age: 65-75 mg/day
Special Cases:
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Elderly Patients: The RDA for elderly individuals is the same as younger adults. Dose adjustments may be necessary in cases of renal impairment.
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Patients with Renal Impairment: Dose reduction may be needed depending on the severity of the impairment.
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Patients with Hepatic Dysfunction: No specific dosage adjustments are typically recommended.
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Patients with Comorbid Conditions: Consult current medical guidelines based on the specific comorbid condition.
Clinical Use Cases
Dosing in clinical settings like intubation, surgical procedures, mechanical ventilation, ICU use, and emergency situations depends on the patient’s specific needs and is typically at the discretion of the treating physician. No general guidelines are available.
Dosage Adjustments
Dose modifications might be necessary for patients with renal/hepatic dysfunction, metabolic disorders, or genetic polymorphisms affecting drug metabolism.
Side Effects
Common Side Effects
Diarrhea, constipation, nausea, vomiting, abdominal cramps, heartburn.
Rare but Serious Side Effects
Kidney stones, painful urination, pink/bloody urine, allergic reactions (rash, itching/swelling, severe dizziness, trouble breathing).
Long-Term Effects
Long-term use of high doses may potentially increase the risk of kidney stones.
Adverse Drug Reactions (ADR)
Allergic reactions and kidney stones.
Contraindications
Hypersensitivity to calcium ascorbate, hypercalcemia, hyperphosphatemia, hypoparathyroidism, history of kidney stones, G6PD deficiency.
Drug Interactions
Quinolone antibiotics, tetracycline antibiotics, thyroid medications, bisphosphonates, aluminum-containing antacids, aspirin, warfarin, oral contraceptives, deferoxamine, iron supplements, and several other medications. It’s crucial to check for interactions with any concomitant medications.
Pregnancy and Breastfeeding
Calcium ascorbate is generally considered safe during pregnancy and breastfeeding when taken within the RDA. Higher doses should be used with caution and under medical supervision.
Drug Profile Summary
- Mechanism of Action: Antioxidant, enzyme cofactor, enhances iron absorption.
- Side Effects: GI disturbances, kidney stones (rare).
- Contraindications: Hypersensitivity, hypercalcemia, kidney stones.
- Drug Interactions: Numerous drug interactions; refer to drug interaction resources.
- Pregnancy & Breastfeeding: Generally safe at RDA doses.
- Dosage: See detailed dosage section.
- Monitoring Parameters: Monitor for signs of GI upset, allergic reactions, and symptoms of hypercalcemia. If used for scurvy, monitor symptom resolution.
Popular Combinations
Often combined with other vitamins and minerals in multivitamin formulations, or with other antioxidants like Vitamin E and ferulic acid for enhanced skin protection.
Precautions
Screen for allergies, metabolic disorders, and organ dysfunction. Evaluate current medications for potential interactions. Patients with a history of kidney stones or renal impairment should be monitored closely.
FAQs (Frequently Asked Questions)
Q1: What is the recommended dosage for Calcium ascorbate?
A: See the detailed dosage section above, as it depends upon age, sex, and pregnancy/lactation status.
Q2: What are the common side effects?
A: Common side effects include diarrhea, constipation, nausea, vomiting, abdominal cramps, and heartburn.
Q3: What are the serious side effects?
A: Serious side effects include allergic reactions, kidney stones, and difficulty urinating.
Q4: Who should not take calcium ascorbate?
A: Individuals with hypercalcemia, hypersensitivity to ascorbate, or a history of kidney stones should avoid it.
Q5: Can I take it during pregnancy?
A: Yes, generally considered safe at RDA doses. Consult with your doctor before taking high doses.
Q6: Does it interact with other medications?
A: Yes, numerous drug interactions exist. Review the detailed Drug Interactions section and check for specific interactions.
Q7: How does calcium ascorbate differ from ascorbic acid?
A: Calcium ascorbate is a buffered form of ascorbic acid, meaning it is less acidic and gentler on the stomach.
Q8: How does it work as an antioxidant?
A: It neutralizes free radicals, preventing oxidative stress and cellular damage.
Q9: Can calcium ascorbate treat or prevent colds?
A: Some evidence suggests it may reduce the duration and severity of colds, but more research is needed. It is not a proven cure.
Q10: What should I monitor while taking calcium ascorbate?
A: Monitor for gastrointestinal side effects, allergic reactions, and signs of hypercalcemia. If taken for scurvy, monitor for symptom resolution. If on other medications, monitor for potential drug interactions.
