Initial Management of Regular (Non-Venomous) Spider Bites
For a suspected regular spider bite, provide local wound care with thorough irrigation, ice application for pain relief, over-the-counter analgesics, and reassurance—antibiotics are NOT indicated unless clear signs of secondary infection develop. 1
Immediate First Aid
Wound cleaning and local care are the cornerstones of initial management:
- Thoroughly irrigate the bite wound with copious amounts of warm or room temperature potable water until all foreign matter is removed 1, 2
- Apply antibiotic ointment and cover with a clean occlusive dressing to improve healing and reduce infection risk 1, 2
- Remove rings and any constricting objects from the affected extremity immediately, as swelling may occur 1, 2
- Elevate the affected area to reduce swelling and accelerate healing 2
Pain and Symptom Management
Most spider bites require only symptomatic treatment:
- Apply ice to the bite site with a clean barrier between ice and skin for local pain relief 1, 2
- Use over-the-counter acetaminophen or NSAIDs for pain control 1, 2
- Apply topical lidocaine 5% if the skin is intact for additional pain relief 2
- Oral antihistamines can reduce itching and swelling 3, 2
- Cold compresses help reduce local pain and swelling 3, 2
For large local reactions with extensive swelling, a short course of oral corticosteroids may be considered, though definitive proof of efficacy through controlled studies is lacking 3, 2
Critical Pitfall: When NOT to Use Antibiotics
This is the most common error in spider bite management:
- Large swelling occurring in the first 24-48 hours is caused by allergic inflammation and mediator release, NOT infection—antibiotics are not indicated 3, 2
- Universal prophylactic antibiotics are not recommended for bite wounds 2
- The swelling and even lymphangitis are caused by mediator release, not infection, making antibiotics inappropriate unless secondary infection develops 3
Antibiotics ARE indicated only when true secondary infection is present:
- Progressive erythema extending beyond the initial bite site 2
- Purulent discharge 2
- Systemic signs of infection such as fever or elevated white blood cell count 2
- For confirmed secondary bacterial infection, use trimethoprim-sulfamethoxazole or doxycycline as first-line therapy to cover MRSA 2
What NOT to Do
Avoid these common harmful interventions:
- Do not apply suction to the bite site—this is ineffective and potentially harmful 1, 2
- Do not apply tourniquets or pressure immobilization bandages, as these may worsen tissue injury 1, 2
- Do not close infected wounds 2
- Do not assume antibiotics are needed for swelling around the bite site 1
When to Seek Urgent Medical Care
Patients should seek immediate medical attention if:
- Pain extends beyond the bite site or becomes severe 1, 2
- Pain is not controlled by over-the-counter medications 1, 2
- An open wound develops 1, 2
- Signs of infection appear (progressive erythema, purulent discharge, fever) 1, 2
- Systemic symptoms develop, including difficulty breathing, muscle rigidity, dizziness, or confusion 1, 2
Expected Course and Follow-Up
Most spider bites have an excellent prognosis:
- Most patients with local symptoms only will recover completely within 24-48 hours 1, 2
- Continue pain management with over-the-counter medications as needed for several days 1, 2
- Follow-up within 24 hours either by phone or office visit is advised 2
- Monitor for signs of secondary infection requiring prompt medical attention 1
Special Consideration: Brown Recluse Spider
If the spider is identified as a brown recluse (which is uncommon and requires actual spider identification), the management remains primarily supportive 2, 4. Research shows that serious complications are rare (only 3% required skin grafting in one series), and the vast majority of bites heal with supportive care alone 4. Aggressive medical therapy does not appear warranted, as long-term outcomes are generally good 4.