Ascorbic acid
Vitamins
Vitamins
Vitamin C. Needed to build collagen and absorb plant iron; the body cannot make or store it. Its lack causes scurvy.
Also called: vitamin C
Quick facts
- Group
- Vitamins
- Target
- Cofactor for collagen formation; antioxidant
- Used for
- Scurvy · Low intake or malabsorption
- Key effects
- Diarrhoea · Headache
- Monitor
- Healing of gum bleeding
- ATC
- A11GA01
No doses: the clinician sets them by the current guideline.
Mechanism of action
Ascorbic acid is needed to make stable collagen for skin, tendons, ligaments, blood vessels, gums and scars. It also keeps iron from plant foods in a form the gut absorbs and acts as an antioxidant. Humans cannot make vitamin C, so a long time without it leads to fragile vessels and poor healing (scurvy).
- Vitamin C is needed to make stable collagen
- Vessels, gums and scars stay strong
- It also helps the gut absorb plant iron
Indications
- Scurvy, treatment and prevention Scurvy (vitamin C deficiency) →
- Low intake or malabsorption (restricted diets, cancer, kidney disease)
Adverse effects
Common
- Diarrhoea, nausea, heartburn, gas
- Headache, flushing, tiredness, trouble sleeping
Contraindications
- Allergy to the product or its ingredients
- Large supplemental doses are not recommended in pregnancy
- Some forms contain sodium (relevant on a low-sodium diet)
Key interactions
- Iron from plant foods or oral iron
- Vitamin C increases its absorption
- Laboratory tests, including urine glucose tests
- Vitamin C can alter results; the lab is told about it
- Smoking
- Lowers vitamin C levels and raises requirements
What is monitored
- Healing of gum bleeding, bruising and wounds in scurvy
- Diet history and malabsorption
Pregnancy and breastfeeding
Vitamin C is needed in pregnancy, but large supplemental doses are not recommended.
Nursing care
- Look for signs of scurvy: bleeding gums, easy bruising, slow wound healing, swollen joints.
- Ask about restricted diets, alcohol, smoking and older age with poor intake.
- People with diabetes ask which urine glucose test to use, since vitamin C can interfere.
Pharmacokinetics
- Absorption
- Absorbed by mouth; also available as an injection
- Distribution
- Not stored in meaningful amounts, so it must come from the diet every day
Test yourself
Think of the answer, then tap the question to see it.
Why does vitamin C deficiency cause bleeding gums and poor wound healing?
Without vitamin C the body cannot make stable collagen, so vessels and scars are weak.
How does vitamin C affect iron?
It increases absorption of iron from plant foods.
Which group is typically affected by scurvy today?
Malnourished older adults and people with very restricted diets.
Connections
Educational content on how drugs work; not a prescribing guide and no substitute for a health professional's advice. No doses are given.
Sources: Ascorbic Acid (Vitamin C): MedlinePlus Drug Information (MedlinePlus (U.S. National Library of Medicine), 2024); Vitamin C: MedlinePlus Medical Encyclopedia (MedlinePlus (U.S. National Library of Medicine), 2026); ATCDDD - ATC/DDD Index (WHO Collaborating Centre for Drug Statistics Methodology, 2026).
Spotted a mistake?We are always improving for the community. Tell us what is wrong and our team will review it.Report a mistake
Representative model, for educational purposes only.