Vitamin C

Uses

Vitamin C is used for prevention and treatment of scurvy. It may be used for pregnancy, lactation, infection, trauma, burns, cold exposure, following surgery, fever, stress, peptic ulcer, cancer, methaemoglobinaemia and in infants receiving unfortified formulas. It is also prescribed for haematuria, dental caries, pyorrhea, acne, infertility, atherosclerosis, fractures, leg ulcers, hay fever, vascular thrombosis prevention, levodopa toxicity, succinyl-choline toxicity, arsenic toxicity etc. To reduce the risk of stroke in the elderly, long-term supplementation with Vitamin C is essential.

Vitamin C is also used to associated treatment for these conditions: Common Cold, Deficiency, Vitamin A, Deficiency, Vitamin D, Fever, Flu caused by Influenza, Folate deficiency, Iron Deficiency (ID), Iron Deficiency Anemia (IDA), Oral bacterial infection, Scurvy, Vitamin C Deficiency, Vitamin Deficiency, Nutritional supplementation, Vitamin supplementation

How Vitamin C works

In humans, an exogenous source of ascorbic acid is required for collagen formation and tissue repair by acting as a cofactor in the posttranslational formation of 4-hydroxyproline in -Xaa-Pro-Gly- sequences in collagens and other proteins. Vitamin C is reversibly oxidized to dehydroascorbic acid in the body. These two forms of the vitamin are believed to be important in oxidation-reduction reactions. The vitamin is involved in tyrosine metabolism, conversion of folic acid to folinic acid, carbohydrate metabolism, synthesis of lipids and proteins, iron metabolism, resistance to infections, and cellular respiration.

Dosage

Vitamin C dosage

vitamin C is usually administered orally. When oral administration is not feasible or when malabsorption is suspected, the drug may be administered IM, IV, or subcutaneously. When given parenterally, utilization of the vitamin reportedly is best after IM administration and that is the preferred parenteral route.

For intravenous injection, dilution into a large volume parenteral such as Normal Saline, Water for Injection, or Glucose is recommended to minimize the adverse reactions associated with intravenous injection.

The average protective dose of vitamin C for adults is 70 to 150 mg daily. In the presence of scurvy, doses of 300 mg to 1 g daily are recommended. However, as much as 6 g has been administered parenterally to normal adults without evidence of toxicity.

To enhance wound healing, doses of 300 to 500 mg daily for a week or ten days both preoperatively and postoperatively are generally considered adequate, although considerably larger amounts have been recommended. In the treatment of burns, doses are governed by the extent of tissue injury. For severe burns, daily doses of 1 to 2 g are recommended. In other conditions in which the need for vitamin C is increased, three to five times the daily optimum allowances appear to be adequate.

Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration, whenever the solution and container permit.

Side Effects

Vitamin C does not seem to have any important adverse effects at dosages less than 4 mg/day. Larger dose may cause diarrhoea or formation of renal calculi of calcium oxalate in patients with renal impairment. Ingestion of more than 600 mg daily have a diuretic action.

Precaution

Ingestion of megadose (more than 1000 mg daily) of vitamin C during pregnancy has resulted in scurvy in neonates. Vitamin C in mega-doses has been contraindicated for patients with hyperoxaluria. Vitamin C itself is a reactive substance in the redox system and can give rise to false positive reactions in certain analytical tests for glucose, uric acid, creatine and occult blood.

Interaction

Potentially hazardous interactions: Vitamin C is incompatible in solution with aminophylline, bleomycin, erythromycin, lactobionate, nafcillin, nitrofurantoin sodium, conjugated oestrogen, sodium bicarbonate, sulphafurazole diethanolamine, chloramphenicol sodium succinate, chlorthiazide sodium and hydrocortisone sodium succinate.

Useful interactions: Vitamin C increases the apparent half-life of paracetamol and enhances iron absorption from the gastrointestinal tract.

Food Interaction

• Avoid multivalent ions. Do not infuse with elemental compounds that can be reduced, such as copper.

Elimination Route

70% to 90%

Half Life

16 days (3.4 hours in people who have excess levels of vitamin C)

Pregnancy & Breastfeeding use

The drug is safe in normal doses in pregnant women, but a daily intake of 5 gm or more is reported to have caused abortion. The drug may be taken safely during lactation.

Storage Condition

Should be stored in a dry place below 30˚C.

Innovators Monograph

You find simplified version here Vitamin C