Most brown recluse bites heal on their own within a few weeks with basic wound care. The median healing time is 17 days, and only about 21% of bites result in permanent scarring. That said, some bites progress to serious tissue damage, so knowing when simple care is enough and when you need medical attention matters.
First Aid Right After the Bite
Brown recluse bites are painless at first, so you may not notice one until redness or swelling appears. Once you suspect a bite, start with these steps:
- Clean the wound with mild soap and water.
- Apply a cool compress for 15 minutes each hour. A clean cloth dampened with cold water or wrapped around ice works well. This reduces both pain and swelling.
- Elevate the area if the bite is on an arm or leg. Keeping it above heart level helps limit swelling.
That’s the core of initial treatment. Don’t apply baking soda, lemon juice, salt, charcoal, or other popular home remedies to the wound. None of these are effective, and some can irritate already-damaged skin.
What Happens as the Bite Progresses
In the hours after a bite, you may notice a growing area of redness around the site. Over the next day or two, the skin can bruise, and a fluid-filled blister may form at the center. In a smaller number of cases, the tissue beneath the blister dies and an open sore develops. This necrotic wound can take weeks to months to fully close, and it sometimes leaves a scar.
Not every bite follows this path. Many brown recluse bites cause only mild irritation that resolves without complications. The venom affects people differently depending on the amount injected and individual immune response.
When the Bite Needs Medical Attention
A bite that stays red and mildly swollen can usually be managed at home. But certain signs mean you should get to a doctor promptly. An expanding area of darkening skin around the bite suggests tissue death is underway. An open wound that isn’t improving after several days also warrants evaluation.
More concerning are systemic symptoms, which indicate the venom is affecting your whole body rather than just the bite site. These can include fever, chills, nausea, vomiting, joint pain, and a widespread rash. In rare but serious cases, the venom breaks down red blood cells, which can lead to kidney damage. If you develop any combination of fever, dark urine, or feel generally ill after a suspected bite, seek emergency care.
What Doctors Actually Do for These Bites
Medical treatment for brown recluse bites is surprisingly conservative. There’s no widely available antivenom in the United States, so care focuses on managing the wound and preventing infection. Your doctor will clean and dress the wound, monitor its progression, and may prescribe pain relief.
Two treatments that sound logical but actually make things worse are systemic corticosteroids and a drug called dapsone. Research published in the Journal of the American Board of Family Practice found that corticosteroids were associated with 28% longer healing times, while dapsone was linked to 45% longer healing and a significantly higher chance of permanent scarring. The type of inflammation caused by brown recluse venom simply doesn’t respond well to these medications.
For bites that develop significant tissue death, a surgeon may need to remove the dead tissue. This typically doesn’t happen in the first week. In one documented case, dead tissue was excised 11 days after the bite, requiring skin grafting over a 5-inch area. Doctors generally wait because operating too early, before the boundaries of dead tissue are clear, can remove healthy tissue unnecessarily and worsen outcomes.
Hyperbaric Oxygen for Severe Cases
For bites with significant necrosis, some treatment centers offer hyperbaric oxygen therapy, where you breathe pure oxygen in a pressurized chamber. A case series found that patients receiving daily 90-minute sessions showed substantial reductions in inflammation, an 88% reduction in pain, and faster wound closure. The therapy appears to speed the formation of new tissue in the wound bed. Sessions typically run 8 to 16 days depending on severity. This isn’t standard first-line treatment, but it’s an option worth discussing with your doctor if a bite isn’t healing well.
Make Sure It’s Actually a Brown Recluse Bite
This might be the most important section of this article. Brown recluse spider bites are dramatically overdiagnosed. A large study of emergency department patients with skin infections found that 59% of cases initially suspected as spider bites were actually MRSA, a bacterial staph infection that needs antibiotics rather than wound monitoring.
Brown recluse spiders live only in the Southwest and Midwest United States. If you’re outside that range, the chances of a brown recluse bite are essentially zero. Even within their territory, a reliable diagnosis requires either catching the spider in the act or bringing in the spider for identification. Many skin conditions mimic the appearance of a spider bite, including boils, tick bites, and medication reactions.
This distinction matters because MRSA and brown recluse bites require completely different treatment. MRSA needs targeted antibiotics. A brown recluse bite needs wound care and time. If you’re assuming “spider bite” without having seen the spider, ask your doctor to test for bacterial infection before settling on a treatment plan.
What Recovery Looks Like
Most people with confirmed brown recluse bites recover fully within two to three weeks. The bite site may remain discolored for a while longer, but the roughly 79% of people who don’t scar will see the area return to normal over time. Keep the wound clean and covered during healing, watch for signs of secondary infection like increasing warmth, pus, or red streaking, and avoid picking at scabs or blisters that form over the site.
For the smaller percentage of bites that develop into open wounds, healing can stretch to several months. These wounds are managed like any slow-healing skin injury: regular cleaning, appropriate dressings, and follow-up visits to monitor progress. If a wound stalls or worsens despite good care, that’s when surgical options or hyperbaric oxygen enter the picture.