Antibiotics for Sea Urchin Stings
Antibiotics are NOT routinely indicated for sea urchin stings unless there are clear signs of secondary bacterial infection, such as increasing pain, redness, warmth, purulent discharge, fever, or cellulitis. 1, 2
Initial Management Priority
The primary treatment for sea urchin injuries focuses on immediate spine removal and heat application, NOT antibiotics 2, 3:
- Immerse the affected area in non-scalding hot water (as hot as tolerated, approximately 40-45°C) for 30-90 minutes to inactivate heat-labile toxins and reduce pain 2, 3
- Remove all visible spines promptly - delayed or incomplete removal increases the risk of granulomatous reactions, synovitis, and chronic complications 1, 4, 3
- Irrigate wounds thoroughly with copious amounts of water to remove foreign matter and reduce contamination 5
When Antibiotics ARE Indicated
Antibiotics should be prescribed when there is evidence of secondary bacterial infection or high-risk wound characteristics 1, 2:
Signs requiring antibiotic treatment:
- Cellulitis (erythema, warmth, tenderness spreading beyond the puncture site) 1
- Purulent discharge 5
- Fever or systemic symptoms 1
- Wounds near joints or deep structures 4, 2
- Delayed presentation (>24-48 hours) with signs of infection 1
Antibiotic Selection for Infected Sea Urchin Wounds
For marine environment injuries with infection, use doxycycline PLUS ceftazidime, OR a fluoroquinolone (ciprofloxacin or levofloxacin) alone 2:
First-line regimens for saltwater injuries:
- Doxycycline 100 mg PO twice daily PLUS ceftazidime (covers Vibrio species, Pseudomonas, and other marine pathogens) 2
- Ciprofloxacin 500-750 mg PO twice daily (alternative monotherapy) 2
- Levofloxacin 500-750 mg PO daily (alternative monotherapy) 2
Duration:
- 5-7 days for uncomplicated soft tissue infections 6
- 3-4 weeks for complications like synovitis or osteomyelitis 6, 4
Wound Care Essentials
After heat treatment and spine removal 5, 3:
- Apply antibiotic ointment and clean occlusive dressing 5
- Do NOT primarily close sea urchin puncture wounds - closure can lead to abscess formation 5
- Ensure tetanus prophylaxis is current 5
Critical Pitfalls to Avoid
- Do NOT use antibiotics prophylactically in clean wounds without infection signs - the inflammatory response is typically from retained spines and toxins, not bacterial infection 1, 7
- Do NOT delay spine removal - aggressive early removal prevents granuloma formation and chronic complications 1, 3
- Do NOT use inadequate antibiotic coverage - avoid first-generation cephalosporins or agents without marine pathogen coverage if infection is present 6, 2
- Do NOT miss deep complications - obtain imaging (MRI if needed) for wounds near joints showing persistent symptoms beyond expected timeframe 4, 3