In the U.S.—

In Canada—

• Deferoxamine adjunct, chronic iron overdose
• Diagnostic aid adjunct, red blood cell disease
• Methemoglobinemia, idiopathic, therapy adjunct
• Nutritional supplement, vitamin

Vitamins ( VYE-ta-mins) are compounds that you must have for growth and health. They are needed in small amounts only and are usually available in the foods that you eat. Ascorbic ( a-SKOR-bik) acid, also known as vitamin C, is necessary for wound healing. It is needed for many functions in the body, including helping the body use carbohydrates, fats, and protein. Vitamin C also strengthens blood vessel walls.

Lack of vitamin C can lead to a condition called scurvy, which causes muscle weakness, swollen and bleeding gums, loss of teeth, and bleeding under the skin, as well as tiredness and depression. Wounds also do not heal easily. Your health care professional may treat scurvy by prescribing vitamin C for you.

Some conditions may increase your need for vitamin C. These include:

• AIDS (acquired immune deficiency syndrome)
• Alcoholism
• Burns
• Cancer
• Diarrhea (prolonged)
• Fever (prolonged)
• Infection (prolonged)
• Intestinal diseases
• Overactive thyroid (hyperthyroidism)
• Stomach ulcer
• Stress (continuing)
• Surgical removal of stomach
• Tuberculosis

Also, the following groups of people may have a deficiency of vitamin C:

• Infants receiving unfortified formulas
• Smokers
• Patients using an artificial kidney (on hemodialysis)
• Patients who undergo surgery
• Individuals who are exposed to long periods of cold temperatures

Increased need for vitamin C should be determined by your health care professional.

Vitamin C may be used for other conditions as determined by your health care professional.

Claims that vitamin C is effective for preventing senility and the common cold, and for treating asthma, some mental problems, cancer, hardening of the arteries, allergies, eye ulcers, blood clots, gum disease, and pressure sores have not been proven. Although vitamin C is being used to reduce the risk of cardiovascular disease and certain types of cancer, there is not enough information to show that these uses are effective.

Injectable vitamin C is given by or under the supervision of a health care professional. Other forms of vitamin C are available without a prescription.

Vitamin C is available in the following dosage forms:

Oral
• Extended-release capsules (U.S.)
• Oral solution (U.S.)
• Syrup (U.S.)
• Tablets (U.S. and Canada)
• Chewable tablets (U.S. and Canada)
• Effervescent tablets (U.S.)
• Extended-release tablets (U.S. and Canada)

Parenteral
• Injection (U.S.)

Vitamins alone will not take the place of a good diet and will not provide energy. Your body also needs other substances found in food such as protein, minerals, carbohydrates, and fat. Vitamins themselves often cannot work without the presence of other foods.

The daily amount of vitamin C needed is defined in several different ways.

For U.S.—
• Recommended Dietary Allowances (RDAs) are the amount of vitamins and minerals needed to provide for adequate nutrition in most healthy persons. RDAs for a given nutrient may vary depending on a person's age, sex, and physical condition (e.g., pregnancy).
• Daily Values (DVs) are used on food and dietary supplement labels to indicate the percent of the recommended daily amount of each nutrient that a serving provides. DV replaces the previous designation of United States Recommended Daily Allowances (USRDAs).

For Canada—
• Recommended Nutrient Intakes (RNIs) are used to determine the amounts of vitamins, minerals, and protein needed to provide adequate nutrition and lessen the risk of chronic disease.

Normal daily recommended intakes for vitamin C are generally defined as follows:

If you are taking this dietary supplement without a prescription, carefully read and follow any precautions on the label. For vitamin C, the following should be considered:

Allergies—Tell your health care professional if you have ever had any unusual or allergic reaction to ascorbic acid. Also, tell your health care professional if you are allergic to any other substances, such as foods, sulfites or other preservatives, or dyes.

Pregnancy—It is especially important that you are receiving enough vitamins when you become pregnant and that you continue to receive the right amount of vitamins throughout your pregnancy. Healthy fetal growth and development depend on a steady supply of nutrients from mother to fetus.

However, taking too much vitamin C daily throughout pregnancy may harm the fetus.

Breast-feeding—It is especially important that you receive the right amounts of vitamins so that your baby will also get the vitamins needed to grow properly. You should also check with your doctor if you are giving your baby an unfortified formula. In that case, the baby must get the vitamins needed some other way. However, taking large amounts of a dietary supplement while breast-feeding may be harmful to the mother and/or baby and should be avoided.

Children—Problems in children have not been reported with intake of normal daily recommended amounts.

Older adults—Problems in older adults have not been reported with intake of normal daily recommended amounts.

Other medicines—Medicines or other dietary supplements

Although certain medicines or dietary supplements should not be used together at all, in other cases they may be used together even if an interaction might occur. In these cases, your health care professional may want to change the dose, or other precautions may be necessary. Tell your health care professional if you are taking any other dietary supplement or any prescription or nonprescription (over-the-counter [OTC]) medicine.

• Blood problems—High doses of vitamin C may cause certain blood problems

• Diabetes mellitus (sugar diabetes)—Very high doses of vitamin C may interfere with tests for sugar in the urine

• Glucose-6-phosphate dehydrogenase (G6PD) deficiency—High doses of vitamin C may cause hemolytic anemia

• Kidney stones (history of)—High doses of vitamin C may increase risk of kidney stones in the urinary tract

Dosing—

The amount of vitamin C needed to meet normal daily recommended intakes will be different for different individuals. The following information includes only the average amounts of vitamin C.

• For oral dosage form (capsules, tablets, oral solution, syrup):
  • To prevent deficiency, the amount taken by mouth is based on normal daily recommended intakes:
    For the U.S.
    • Adult and teenage males—50 to 60 milligrams (mg) per day.
    • Adult and teenage females—50 to 60 mg per day.
    • Pregnant females—70 mg per day.
    • Breast-feeding females—90 to 95 mg per day.
    • Smokers—100 mg per day.
    • Children 4 to 10 years of age—45 mg per day.
    • Children birth to 3 years of age—30 to 40 mg per day.
    For Canada
    • Adult and teenage males—25 to 40 mg per day.
    • Adult and teenage females—25 to 30 mg per day.
    • Pregnant females—30 to 40 mg per day.
    • Breast-feeding females—55 mg per day.
    • Smokers—45 to 60 mg per day.
    • Children 4 to 10 years of age—25 mg per day.
    • Children birth to 3 years of age—20 mg per day.
  • To treat deficiency:
    • Adults and teenagers—Treatment dose is determined by prescriber for each individual based on the severity of deficiency. The following dose has been determined for scurvy: 500 mg a day for at least 2 weeks.
    • Children—Treatment dose is determined by prescriber for each individual based on the severity of deficiency. The following dose has been determined for scurvy: 100 to 300 mg a day for at least 2 weeks.

For those individuals taking the oral liquid form of vitamin C:

• This preparation is to be taken by mouth even though it comes in a dropper bottle.
• This dietary supplement may be dropped directly into the mouth or mixed with cereal, fruit juice, or other food.

Missed dose—

If you miss taking a vitamin for one or more days there is no cause for concern, since it takes some time for your body to become seriously low in vitamins. However, if your health care professional has recommended that you take this vitamin, try to remember to take it as directed every day.

Storage—

To store this dietary supplement:

• Keep out of the reach of children.
• Store away from heat and direct light.
• Do not store in the bathroom, near the kitchen sink, or in other damp places. Heat or moisture may cause the dietary supplement to break down.
• Keep the oral liquid form of this dietary supplement from freezing.
• Do not keep outdated dietary supplements or those no longer needed. Be sure that any discarded dietary supplement is out of the reach of children.

Vitamin C is not stored in the body. If you take more than you need, the extra vitamin C will pass into your urine. Very large doses may also interfere with tests for sugar in diabetics and with tests for blood in the stool.

Along with its needed effects, a dietary supplement may cause some unwanted effects. Although not all of these side effects may occur, if they do occur, they may need medical attention.

Check with your health care professional as soon as possible if the following side effect occurs:

• Less common or rare--with high doses
  • Side or lower back pain 
  
  

Other side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the dietary supplement. However, check with your health care professional as soon as possible if any of the following side effects continue or are bothersome:

• Less common or rare--with high doses
  • Diarrhea;  dizziness or faintness (with the injection only);  flushing or redness of skin;  headache;  increase in urination (mild) ;  nausea or vomiting;  stomach cramps 
  
  

Other side effects not listed above may also occur in some individuals. If you notice any other effects, check with your health care professional.

Once a medicine or dietary supplement has been approved for marketing for a certain use, experience may show that it is also useful for other medical problems. Although these uses are not included in product labeling, vitamin C is used in certain patients with the following medical conditions:

• Overdose of iron (to help another drug in decreasing iron levels in the body)
• Methemoglobinemia (a blood disease)

Other than the above information, there is no additional information relating to proper use, precautions, or side effects for these uses.