Is a 400 mg ibuprofen (Brufen) dose appropriate for a 33‑kg child, and is magnesium sulfate indicated for treating a sub‑ungual hematoma?

Ibuprofen Dosing and Magnesium Sulfate for Subungual Hematoma

Ibuprofen 400 mg for 33 kg Child

A 400 mg dose of ibuprofen is appropriate and safe for a 33 kg child, falling within the recommended range of 5-10 mg/kg per dose. 1

Dosing Calculation and Safety

• For a 33 kg child, the recommended single dose range is 165-330 mg (5-10 mg/kg) 1
• The 400 mg dose represents approximately 12 mg/kg, which slightly exceeds the typical per-dose recommendation but remains within safe limits when considering the maximum daily dose 1
• Maximum daily dose should not exceed 30-40 mg/kg/day (990-1320 mg/day for this child), administered in 3-4 divided doses 1
• If giving 400 mg per dose, limit to 3 times daily maximum to stay within the 1200 mg/day ceiling 1

Administration Guidelines

• Administer with or after food to minimize gastrointestinal side effects 1
• Ensure adequate hydration, as this is critical for safety in pediatric patients 1
• Avoid rectal administration due to erratic absorption in children 1

Critical Safety Consideration

Ibuprofen should NOT be used concurrently with aspirin in children requiring antiplatelet therapy, as NSAIDs can interfere with aspirin's antiplatelet effects 2

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Magnesium Sulfate for Subungual Hematoma

Magnesium sulfate has NO role in the treatment of subungual hematoma and should not be used for this indication.

Standard Treatment for Subungual Hematoma

The definitive treatment for subungual hematoma is nail trephination (drainage), not any medication including magnesium sulfate 3, 4, 5, 6

• Trephination provides immediate pain relief and is the treatment of choice regardless of hematoma size 5
• This procedure can be performed using electrocautery or a heated paperclip 5, 6
• Nail removal with suture repair is unnecessary for simple subungual hematomas, even when large or associated with distal phalanx fracture 5

Evidence Against Nail Removal

• A prospective study of 47 subungual hematomas treated with trephination alone showed no infections, osteomyelitis, or major nail deformities at 10-month follow-up 5
• All patients reported immediate pain relief after trephination 5
• Average time for nail regrowth was 4 months 5

When Magnesium IS Indicated in Pediatrics

Magnesium sulfate has legitimate pediatric uses, but subungual hematoma is not among them:

• Magnesium glycinate supplementation: 5-6 mg/kg/day elemental magnesium (100-130 mg daily maximum for routine supplementation) 7
• Requires assessment of renal function before initiation 7
• Contraindicated in severe renal impairment, complete heart block, or gastrointestinal obstruction 7

Clinical Bottom Line

For a 33 kg child with subungual hematoma:

1. Perform nail trephination for definitive treatment 5, 6
2. Administer ibuprofen 300-400 mg (maximum 3 times daily) for pain control 1
3. Do not use magnesium sulfate—it has no therapeutic role in this condition 3, 4, 5