What is the appropriate management for a patient with glucose‑6‑phosphate dehydrogenase deficiency who presents with a severe common cold (upper‑respiratory viral infection)?

Management of Severe Cold in G6PD-Deficient Patients

Direct Answer

For a patient with G6PD deficiency presenting with a severe common cold, provide supportive care with standard over-the-counter medications that are safe in G6PD deficiency, avoid all oxidant drugs, and educate the patient to monitor for signs of hemolysis triggered by the infection itself. 1, 2

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Key Management Principles

Infection as an Oxidative Trigger

• Viral upper respiratory infections themselves can precipitate hemolytic crises in G6PD-deficient patients through oxidative stress, independent of medication exposure. 1, 3
• The severity of hemolysis risk varies by genetic variant: Mediterranean (B-) variants carry higher risk of life-threatening hemolysis compared to African (A-) variants, which typically produce milder, self-limited episodes. 4, 5
• Patients must be educated to recognize early signs of hemolysis: dark urine, sudden fatigue or pallor, jaundice, and abdominal or back pain. 5

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Safe Symptomatic Treatment Options

Medications That Can Be Used Safely

• Benzodiazepines, codeine and codeine derivatives, propofol, fentanyl, and ketamine have not been shown to cause hemolytic crises in G6PD-deficient patients and can be used for symptom management. 1
• Standard analgesics and antipyretics that are not oxidant drugs may be used for fever and discomfort. 1

Medications to Strictly Avoid

• Absolutely contraindicated oxidant drugs include primaquine, rasburicase, methylene blue, and dapsone—these must never be used in G6PD deficiency. 5, 6
• Sulfonamides (including sulfamethoxazole/cotrimoxazole) should be avoided or used with extreme caution, though recent data suggests they may be safer than historically believed. 4

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Clinical Monitoring Strategy

When to Escalate Care

• If the patient develops dark urine, jaundice, severe fatigue, tachycardia, or signs of hemodynamic instability during the viral illness, immediately assess for acute hemolysis with complete blood count, reticulocyte count, lactate dehydrogenase, haptoglobin, and indirect bilirubin. 5
• Record vital signs every 4–6 hours during the initial 24–48 hours if hemolysis is suspected to detect tachycardia or hypotension. 5

Supportive Care for Hemolysis

• Provide aggressive intravenous hydration to maintain urine output ≥100 mL/hour in adults (or ≥3 mL/kg/hour for patients <40 kg) to prevent hemoglobin-induced acute kidney injury. 5
• Transfusion is indicated when hemoglobin falls below 7 g/dL or when the patient develops dyspnea, chest pain, altered mental status, or hemodynamic instability, regardless of absolute hemoglobin value. 5
• For asymptomatic patients with hemoglobin ≥8 g/dL, supportive care and close observation are sufficient without transfusion. 5

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Screening and Prevention

Pre-Treatment Screening

• Qualitative screening for G6PD deficiency is recommended before starting any oxidant drug therapy in patients of Mediterranean, African, Indian, or Southeast Asian descent. 4, 5
• Avoid testing during or immediately after acute hemolytic episodes, as reticulocytes and young red cells may contain near-normal enzyme levels and mask deficiency. 6
• Wait at least 50 days (ideally 120 days) after red cell transfusion before performing enzyme assays to avoid false-negative results from donor cell contamination. 6

Patient Education

• The most effective management strategy is preventing hemolysis by avoiding oxidative stressors, including certain medications, fava beans, and recognizing that infections themselves can trigger crises. 1
• First-degree relatives of G6PD-deficient patients should be screened. 6

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Common Pitfalls to Avoid

• Do not assume that the absence of prior hemolytic episodes means the patient can tolerate oxidant drugs—the Mediterranean variant can cause life-threatening hemolysis on first exposure. 5
• Do not overlook the infection itself as a hemolytic trigger—even without medication exposure, severe viral infections (including COVID-19) have precipitated severe hemolytic crises in G6PD-deficient patients. 3
• Do not use chloroquine or hydroxychloroquine during acute viral illness in G6PD deficiency without careful consideration—while generally considered relatively safe at standard doses, case reports document severe hemolysis when combined with COVID-19 infection. 5, 3