Whitetail Spider Bite Management
Critical Clarification: Whitetail Spiders Are NOT Sicarius Species
The "whitetail spider" (Lampona species from Australia) is completely different from Sicarius spiders, and importantly, whitetail spider bites do NOT cause necrotic ulcers—this is a medical myth that has been thoroughly debunked. 1 When patients present with necrotic ulcers attributed to whitetail spider bites, alternative diagnoses should be aggressively pursued, including bacterial infections (especially Staphylococcus aureus), fungal infections, pyoderma gangrenosum, vasculitis, or Nocardia infection. 1
Initial Management of Suspected Whitetail Spider Bite
Treat whitetail spider bites as non-venomous spider bites with local wound care, pain management, and close monitoring—antibiotics are NOT routinely indicated. 2
Immediate First Aid
Thoroughly irrigate the wound with copious warm or room temperature water until no foreign matter remains in the wound. 2
Apply ice with a clean barrier between ice and skin for local pain relief. 2
Remove rings and constricting objects immediately from the affected extremity, as swelling may occur. 2
Apply antibiotic ointment and cover with a clean occlusive dressing to improve healing and reduce infection risk. 2
Elevate the affected extremity to reduce swelling. 3
Pain Management
Use over-the-counter acetaminophen or NSAIDs for pain control. 2, 3
Apply topical lidocaine 5% if skin is intact for additional pain relief. 3
Critical Pitfall: Antibiotics Are NOT Indicated Initially
Swelling in the first 24-48 hours is caused by inflammatory mediator release, NOT infection, and does NOT require antibiotics. 2, 3 Universal prophylactic antibiotics are not recommended for bite wounds. 3
When to Seek Urgent Medical Care
Patients should seek immediate medical attention if: 2, 3
- Pain extends beyond the bite site or becomes severe
- Pain is not controlled by over-the-counter medications
- An open wound develops
- Signs of secondary bacterial infection appear:
- Progressive erythema extending beyond the initial bite site
- Purulent discharge
- Systemic signs such as fever or elevated white blood cell count 3
- Systemic symptoms develop (difficulty breathing, dizziness, confusion, muscle rigidity)
What NOT to Do
Do NOT apply suction to the bite site—this is ineffective and potentially harmful. 2
Do NOT apply tourniquets or pressure immobilization bandages—these may worsen tissue injury. 2
Do NOT assume antibiotics are needed for swelling around the bite site. 2
Do NOT attribute necrotic ulcers to whitetail spider bites without proper investigation. 1
Antibiotic Therapy (Only If Secondary Infection Confirmed)
If signs of confirmed secondary bacterial infection develop: 3
- First-line oral therapy: Trimethoprim-sulfamethoxazole OR doxycycline (to cover MRSA)
- Alternative: Clindamycin (if local resistance patterns permit)
Investigation of Necrotic Ulcers
If a necrotic ulcer develops, aggressively investigate for alternative diagnoses rather than attributing it to spider bite. 1 Obtain:
- Bacterial cultures (including S. aureus)
- Fungal cultures
- Mycobacterial cultures
- Skin biopsy for histopathology 1
In one prospective case series, ALL cases initially attributed to whitetail spider bites were found to have alternative diagnoses including dermatophytoses, staphylococcal infections, pyoderma gangrenosum, cutaneous polyarteritis nodosa, Nocardia braziliensis, and infected diabetic ulcers. 1
Expected Course and Follow-Up
Most patients with local symptoms only recover completely within 24-48 hours. 2, 3
Continue pain management with over-the-counter medications as needed for several days. 2, 3
Follow-up within 24 hours by phone or office visit is advised. 3
Monitor for signs of secondary infection requiring medical attention. 2