What is the treatment for a patient with iron deficiency anemia, hyperglycemia, hyponatremia, and hyperkalemia?

Treatment Approach for Iron Deficiency Anemia with Metabolic Abnormalities

Start ferrous sulfate 200 mg once daily in the morning on an empty stomach, add vitamin C 500 mg to enhance absorption, and address the concurrent hyperglycemia, hyponatremia, and hyperkalemia as separate but urgent issues. 1

Iron Deficiency Anemia Treatment

Immediate Oral Iron Therapy

• Ferrous sulfate 200 mg once daily is the first-line treatment due to effectiveness and low cost, with once-daily dosing improving tolerability while maintaining efficacy 1
• Take the dose in the morning on an empty stomach for optimal absorption, though taking with food is acceptable if gastrointestinal side effects occur 1
• Add vitamin C (ascorbic acid) 500 mg with each iron dose - this is particularly critical given the severely low iron saturation of 4% and ferritin of 10 ng/mL 1
• If ferrous sulfate is not tolerated, switch to ferrous gluconate or ferrous fumarate, which are equally effective alternatives 1

Expected Response and Monitoring

• Hemoglobin should rise by approximately 2 g/dL after 3-4 weeks of treatment 1
• If no response occurs within 4 weeks, assess for non-adherence, malabsorption, or ongoing blood loss 1
• Continue oral iron therapy for 3 months after anemia correction to fully replenish iron stores 1
• Monitor hemoglobin and red cell indices every 3 months for the first year, then again after another year 1

When to Consider Intravenous Iron

• Switch to IV iron if the patient cannot tolerate at least two different oral iron preparations 1
• IV iron is indicated for inadequate response to oral therapy after 4 weeks, conditions affecting iron absorption (inflammatory bowel disease, celiac disease, post-bariatric surgery), or ongoing gastrointestinal blood loss exceeding oral replacement capacity 1

Identify Underlying Cause

• This patient requires gastrointestinal evaluation - the combination of severe iron deficiency (ferritin 10, iron saturation 4%) in a 72-year-old woman warrants upper endoscopy and colonoscopy to identify occult bleeding sources 1
• Screen for celiac disease with antiendomysial antibody and IgA measurement 1

Critical Concurrent Metabolic Issues

Hyponatremia (Sodium 128 mEq/L)

• This represents moderate hyponatremia requiring urgent evaluation for symptoms (confusion, falls, seizure risk)
• Determine if hypovolemic, euvolemic, or hypervolemic to guide fluid management
• The low creatinine (0.49) suggests possible malnutrition or muscle wasting, which may contribute to hyponatremia

Hyperkalemia (Potassium 5.4 mEq/L)

• This is mild hyperkalemia but requires ECG monitoring and assessment for medications that may be contributing (ACE inhibitors, ARBs, potassium-sparing diuretics, NSAIDs)
• Consider dietary potassium restriction
• The combination with hyponatremia raises concern for adrenal insufficiency or medication effects

Hyperglycemia (Glucose 157 mg/dL)

• Evaluate for diabetes mellitus with hemoglobin A1c
• Initiate dietary modifications and consider metformin if A1c confirms diabetes

Common Pitfalls to Avoid

• Do not prescribe multiple daily doses of iron - this increases side effects without improving efficacy 1
• Do not stop iron therapy when hemoglobin normalizes - continue for 3 months to replenish stores 1
• Do not overlook vitamin C supplementation when iron saturation is severely low 1
• Do not fail to investigate the underlying cause of iron deficiency while supplementing 1
• Do not ignore the hyponatremia and hyperkalemia - these require simultaneous evaluation and may indicate serious underlying conditions

If Treatment Fails

• If anemia does not resolve within 6 months despite appropriate iron therapy, reassess for ongoing blood loss, evaluate for malabsorption syndromes, verify patient adherence, and consider hematology consultation 1