Before Using This Dietary Supplement

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.

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.

Other medical problems—The presence of other medical problems may affect the use of vitamin C. Make sure you tell your health care professional if you have any other medical problems, especially:

• 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