Cephalexin is Safe for G6PD-Deficient Patients
Cephalexin can be safely used in a 1-year-old pediatric patient with G6PD deficiency, as cephalosporins are not among the medications contraindicated in this condition.
Evidence-Based Safety Profile
The most comprehensive evidence-based review of medications in G6PD deficiency identified only seven drugs with solid evidence for prohibition: dapsone, methylthioninium chloride (methylene blue), nitrofurantoin, phenazopyridine, primaquine, rasburicase, and tolonium chloride 1. Cephalexin and other cephalosporins are notably absent from this list 1.
According to guideline-derived medication safety data, only these same seven medications are definitively contraindicated in G6PD deficiency 2. All other medications, including cephalosporins like cephalexin, have no evidence contraindicating their use in normal therapeutic doses 1.
Clinical Use in Pediatric Patients
Cephalexin is explicitly recommended in pediatric infectious disease guidelines for treating methicillin-susceptible Staphylococcus aureus infections in children, with a preferred oral dose of 75-100 mg/kg/day divided into 3 or 4 doses 3. These guidelines make no special restrictions or warnings for G6PD-deficient patients 3.
The drug has demonstrated excellent safety in pediatric populations, with rapid oral absorption, high blood and urine levels, and near absence of side effects 4. It is particularly valuable for susceptible infections in infants and children who do not require parenteral therapy 4.
Important Caveats
Monitor for Infection-Related Hemolysis
While cephalexin itself is safe, the underlying infection being treated may trigger hemolysis in G6PD-deficient patients 1. Many compounds have been wrongly cited as causing hemolysis when they were actually administered during infection-related hemolytic episodes 1.
Variant-Specific Considerations
The severity of G6PD deficiency varies by genetic variant 5, 2:
- Mediterranean variant (Gdmed): More severe reactions, found predominantly in Mediterranean, Indian, and Southeast Asian populations 5
- African variant (GdA-): Milder, self-limited hemolysis, found in 10-15% of Black individuals 5
Clinical Monitoring
When using cephalexin in a G6PD-deficient 1-year-old, monitor for signs of hemolysis including 2:
- Jaundice
- Dark urine
- Fatigue and pallor
- Unexplained anemia
Avoid Confusion with Beta-Lactams
While cephalexin is safe, do not confuse this with other antimicrobials. One case report documented severe hemolysis after amoxicillin exposure in a G6PD-deficient patient 6, though this remains controversial and may have been infection-related 1. The key distinction is that cephalosporins like cephalexin have no documented evidence of causing hemolysis in G6PD deficiency 1.
Practical Dosing
For a 1-year-old child, use standard cephalexin dosing of 75-100 mg/kg/day divided into 3-4 doses for most infections 3. No dose adjustment is needed for G6PD deficiency 1.