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URL of this page: https://medlineplus.gov/druginfo/meds/a682583.html

Ascorbic Acid (Vitamin C)

pronounced as (a skor' bik)

Why is this medication prescribed?

Ascorbic acid (vitamin C) is used as a dietary supplement when the amount of ascorbic acid in the diet is not enough. People most at risk for ascorbic acid deficiency are those with a limited variety of food in their diet, or who have intestinal malabsorption problems from cancer or kidney disease. Ascorbic acid is also used to prevent and treat scurvy (a disease that causes fatigue, gum swelling, joint pain, and poor wound healing from a lack of vitamin C in the body). Ascorbic acid is in a class of medications called antioxidants. It is needed by the body to help wounds heal, to enhance the absorption of iron from plant foods, and to support the immune system. It works as an antioxidant to protect your cells against free radicals, which may play a role in heart disease, cancer and other diseases.

How should this medicine be used?

Ascorbic acid comes in extended-release (long-acting) capsules and tablets, lozenges, chewable tablets, chewable gels (gummies), and liquid drops to be given by mouth. It usually is taken once a day or as directed by your doctor. Ascorbic acid is available without a prescription, but your doctor may prescribe ascorbic acid to treat certain conditions. Follow the directions on the package or on your product label or doctor's instructions carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take ascorbic acid exactly as directed. Do not take more or less of it or take it more often than recommended by your doctor.

It may take up to 4 weeks for symptoms of scurvy to improve.

Ascorbic acid supplements are available alone and in combination with other vitamins.

Other uses for this medicine

This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

What special precautions should I follow?

Before taking ascorbic acid,

  • tell your doctor and pharmacist if you are allergic to ascorbic acid, any other medications, or any of the ingredients in ascorbic acid products. Ask your pharmacist for a list of the ingredients.
  • Tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take while taking ascorbic acid. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
  • tell your doctor if you have or have ever had medical conditions.
  • tell your doctor if you are pregnant, plan to become pregnant, or are breastfeeding. If you become pregnant while taking ascorbic acid, call your doctor.
  • tell your doctor if you use tobacco products. Cigarette smoking may decrease the effectiveness of ascorbic acid and you may need to take a larger dose. Talk to your doctor or pharmacist about your dose of ascorbic acid if you use tobacco products.

What special dietary instructions should I follow?

Some forms of ascorbic acid contain sodium and should be avoided if you are on a sodium- or salt-restricted diet.

What should I do if I forget a dose?

Take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

What side effects can this medication cause?

Ascorbic acid may cause side effects. Tell your doctor if either of these symptoms is severe or does not go away:

  • diarrhea
  • nausea
  • heartburn
  • fatigue
  • flushing
  • headache
  • difficulty falling asleep or staying asleep
  • gas

Ascorbic acid may cause other side effects. Call your doctor if you have any unusual problems while taking this vitamin.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

What should I know about storage and disposal of this medication?

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom).

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. http://www.upandaway.org

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website (http://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.

In case of emergency/overdose

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

What other information should I know?

Keep all appointments with your doctor.

Before having any laboratory test, tell your doctor and the laboratory personnel that you are taking ascorbic acid. Diabetics should talk to their doctor or pharmacist for the correct way to test their urine if they are taking ascorbic acid supplements.

Ask your pharmacist any questions you have about ascorbic acid.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

Brand names

  • C-500® Chewable Tablet
  • C-Time®
  • Cecon® Drops
  • Centrum® Singles-Vitamin C
  • Cevi-Bid®
  • Halls Defense®
  • Sunkist® Vitamin C
Last Revised - 01/15/2024