Vitamin C - Drug Interactions, Side Effects and Precautions of Use
22 August 2007Type of Drug:
Water-soluble vitamin with antioxidant properties. Vitamin not stored by the body.
How the Drug Works:
Vitamin C is involved with several functions in the body, including the following: Utilization of carbohydrates; formation of fats and proteins; maintenance of blood vessels; cell respiration; formation of connective tissues (eg, collagen); promotion of growth, tissue repair, and wound healing; aiding tooth and bone formation; increasing iron absorption; resistance to Infections
Uses:
To prevent and treat scurvy (vitamin C deficiency), characterized by slow wound healing, defects in tooth formation (children), faulty bone development (children), bleeding gums and loose teeth, irritability, easy bruising, joint pain, fatigue, and muscle weakness.
Scurvy is a rare condition in the US. It develops only when psychiatric illness, alcoholism, age, disease of the digestive system, food fads, poverty, or ignorance result in inadequate nutrition. It may also develop in infants whose formulas lack adequate vitamin C.
Unlabeled Uses: Vitamin C may occasionally be used as a supplement in patients with chronic illnesses, infections, conditions with fever, burns, and certain types of blood disorders, and in infants or smokers. It may be used to improve the general health and well-being of institutionalized elderly patients; to promote healing after surgery, trauma, and fractures; to prevent the common cold; to treat asthma; and to decrease recovery time from cold sores, pressure sores, rectal polyps, and other lesions. It is also used as a urinary acidifier at high doses.
Precautions:
Use with caution in the following situations: Kidney stones or a history of kidney stones
Lab test interference: Vitamin C doses over 500 mg may cause falseÂnegative urine sugar results in some tests. Also, vitamin C use 48 to 72 hours before certain types of tests for blood in the stool may cause false-negative results. Use with caution.
Drug interactions: Large doses (more than 2 g/day) may affect the of urine, making it more acidic. Changes in urine pH may cause the effects of other medications to be exaggerated (increased) or may decrease their effectiveness.
Kidney stone formation: Kidney stone formation with vitamin C is more likely if large doses are taken over long periods of time. Symptoms include severe flank pain associated with nausea and vomiting, difficult or painful urination, and blood in the urine.
Pregnancy: Adequate studies have not been done in pregnant women. Use only if clearly needed and potential benefits outweigh the possible hazards to the fetus.
Breastfeeding: Vitamin C appears in breast milk. Consult your doctor before you begin breastfeeding.
Tartrazine: Some of these products may contain the dye tartrazine (FD&C Yellow No.5), which can cause allergic reactions in certain individuals. Check the package label when available or consult your pharmacist or doctor.
Drug Interactions:
Tell your doctor or pharmacist if you are taking or planning to take any overÂthe-counter or prescription medications or dietary supplements with vitamin C. Doses of one or both drugs may need to be modified or a different drug may need to be prescribed. The following drugs and drug classes interact with vitamin C:
- Contraceptives, oral (eg,Ortho-Novum)
- Sulfonamides (eg,Gantrisin)
- Warfarin (eg, Coumadin)
Doses:
|
Type |
Generic Name |
Supplied As |
Generic Available |
|
|
Ascorbic Acid/Vitamin C |
|
|
|
otc |
Vitamin C | Tablets: 250 mg, 500 mg.1000 mg |
Yes |
|
otc |
Vitamin C | Capsules: 750 mg |
Yes |
|
otc |
Cevi-Bid | Capsules, timed-release: 500 mg, 1000 mg |
Yes |
|
otc |
N’ice Vitamin C Drop | Lozenges: 60 mg |
Yes |
|
otc |
Cecon | Oral solution: 100 mg/ml |
Yes |
|
otc |
Dull-C | Powder: 1060 mg/g |
Yes |
|
otc |
Vita-C | Crystals: 100 mg/g |
Yes |
|
otc |
Calcium Ascorbate | Tablets: 500 mg |
Yes |
|
|
Powder: 814 mg/g |
Yes |
Side Effects:
Every drug is capable of producing side effects. Many vitamin C users experience no, or minor, side effects. The frequency and severity of side effects depend on many factors, including dose, duration of therapy, and individual susceptibility. Possible side effects include:
Digestive Tract: Diarrhea; mouth sores; nausea; vomiting; stomach upset; heartburn.
Other: Kidney stones; fatigue; flushing; headache; sleeplessness; sleepiness.
Guidelines for Use:
- Most people on a balanced diet do not need vitamin supplements.
- Recommended Dietary Allowances (RDAs) Â Adults: 60 mg.
- Tablets _ May discolor slightly. This does not affect potency.
- powder/Crystals _ Dissolve the recommended dose in a glass of water or juice.
- Solution _ Add recommended dose to any desired liquid (eg, milk, juice).
- Total vitamin C intake includes the amounts taken in the diet, plus supplements. This total should not substantially exceed the RDA.
- Common sources of vitamin C - Strawberries, citrus fruit, tomatoes, potatoes, leafy vegetables, cabbage greens, and melons.
- Store at controlled room temperature (59 to 86°F). Keep containers tightly closed.
Tagged under:cell respiration, connective tissues, disease of the digestive system, drug interactions, inadequate nutrition, kidney stones, vitamin c, vitamins water soluble vitamin
