What are the symptoms and treatment of vitamin C deficiency?

Vitamin C Deficiency: Symptoms and Treatment

Clinical Presentation of Scurvy

Vitamin C deficiency (scurvy) presents with a characteristic constellation of mucocutaneous and systemic symptoms that develop when plasma levels fall below 11 μmol/L. 1, 2

Classic Symptoms

• Mucocutaneous manifestations: Petechiae, easy bruising (ecchymosis), perifollicular hemorrhages, hyperkeratosis, and corkscrew hairs 2, 3
• Gingival changes: Swollen, bleeding gums and poor dental health 2, 4
• Bleeding complications: Epistaxis, excessive bleeding from minor cuts, and spontaneous hemorrhage 1, 2
• Musculoskeletal symptoms: Myalgias, bone pain, and poor wound healing 5, 4
• Systemic manifestations: Generalized fatigue, apathy, weakness, and anemia 5, 3
• Edema: Bilateral lower extremity edema and episodic anasarca may occur 2

High-Risk Populations

Suspect vitamin C deficiency in patients with: 1, 2, 5

• Malabsorptive disorders (Crohn's disease, celiac disease, chronic diarrhea)
• Inadequate dietary intake (alcohol use disorder, food insecurity, restrictive eating)
• Psychiatric disorders or severe mental illness
• Chronic dialysis or renal impairment
• Bariatric surgery patients

Diagnostic Approach

Plasma vitamin C measurement should be obtained in any patient with clinical suspicion of scurvy or chronic low intake, but do not delay empiric treatment while awaiting results. 6

Important Diagnostic Caveats

• Do NOT measure plasma vitamin C during acute inflammation or critical illness - levels are unreliable when CRP >10 mg/L and undetectable when CRP >40 mg/L 7, 8, 9
• A clinical trial of vitamin C (~1 g/day for at least one week) should not be delayed in the presence of clinical symptoms 6
• Consider broader nutritional assessment if vitamin C deficiency is confirmed, as multiple deficiencies often coexist 2, 5

Treatment Protocols

Oral Treatment (First-Line for Mild-Moderate Deficiency)

For symptomatic vitamin C deficiency without malabsorption, initiate oral supplementation with 100-500 mg daily. 6

• Standard repletion dose: 100 mg three times daily OR 500 mg once daily for 1 month 6
• Maintenance after repletion: Continue with dietary reference intake of 75-90 mg/day 8
• Oral absorption is limited at higher single doses due to saturable intestinal transporters 6, 9

Intravenous Treatment (For Severe Deficiency or Malabsorption)

IV vitamin C is required when oral supplementation fails, malabsorption is present, or severe symptoms demand rapid repletion. 10, 1

IV Dosing Regimens:

• Acute scurvy with severe symptoms: 1-2 g/day IV for 5-7 days, then transition to oral maintenance 6, 9
• Malabsorption syndromes: 200-500 mg/day IV may be required long-term 6, 1
• Critical illness with deficiency: 2-3 g/day IV during acute phase of inflammation 6, 7, 9

Administration Guidelines:

• Dilute with normal saline or 5% dextrose before IV administration 9, 10
• Infuse over 30 minutes for doses ≥1000 mg 10
• Monitor for resolution of bleeding symptoms and cutaneous findings 1, 2

Special Populations

Bariatric surgery patients: Require 200-500 mg/day due to chronic malabsorption risk 6

Patients with chronic oxidative stress (diabetes, heart failure, COPD, smoking, chronic dialysis): Consider 200-500 mg/day prophylactically 6, 9

Critical Safety Considerations

Contraindications and Precautions

Exercise extreme caution or avoid high-dose vitamin C in: 7, 10

• Renal impairment or dialysis patients - increased risk of oxalate nephropathy
• History of oxalate kidney stones - vitamin C metabolizes to oxalate
• G6PD deficiency - risk of hemolysis
• Hemochromatosis - vitamin C enhances iron absorption
• Pediatric patients <2 years - higher risk of oxalate nephropathy due to decreased GFR 10

Monitoring During Treatment

• Assess clinical response (resolution of bleeding, petechiae, fatigue) within 1-2 weeks 1, 2
• Repeat plasma vitamin C levels after 4 weeks if initial treatment fails 1
• If oral supplementation fails despite adequate dosing, suspect malabsorption and consider IV therapy 1, 2

Common Clinical Pitfalls

• Failing to consider scurvy in well-nourished patients - malabsorption can cause deficiency despite adequate intake 2
• Assuming oral supplementation always works - some patients require IV therapy even with high oral doses (2000 mg/day) 1
• Measuring vitamin C levels during acute illness - inflammation falsely lowers levels and complicates interpretation 7, 8
• Overlooking concurrent nutritional deficiencies - vitamin C deficiency often coexists with other micronutrient deficits 5
• Delaying empiric treatment - start vitamin C immediately when scurvy is suspected clinically; do not wait for laboratory confirmation 6