Most spider bites heal on their own in about a week. The vast majority of spiders produce bites no worse than a mosquito bite or bee sting, and the swelling, redness, and itching follow a predictable course. Bites from venomous species like brown recluses or black widows take significantly longer and sometimes require medical care.
Typical Healing Timeline for Common Bites
A bite from a non-venomous house spider generally resolves within five to seven days. In the first 24 to 48 hours, your immune system floods the area with white blood cells to clean out any bacteria or foreign material. That’s the redness and swelling you see. This inflammatory phase lasts roughly six days for any skin wound, and by the end of it, a simple spider bite is usually done.
You may not even realize you were bitten right away. Burning, pain, itching, or redness at the bite site can be delayed, sometimes developing hours or even a day or two after the bite itself. A small red bump may appear, itch for a few days, and fade without any intervention.
Brown Recluse Bites Take Weeks or Months
Brown recluse bites follow a different and more drawn-out pattern. The timeline depends almost entirely on how much venom the spider injected.
Within three to eight hours, the bite area becomes red, sensitive, and feels like it’s burning. The skin may develop a bullseye pattern or turn bluish from bruising. Over the next three to five days, a small-venom bite calms down on its own, and that initial discomfort fades. If more venom was injected, the pain continues spreading and an open ulcer forms at the bite site.
In severe cases, the skin around that ulcer breaks down between seven and 14 days after the bite, creating a wound with dead tissue underneath. The majority of brown recluse bites heal within three weeks, but these necrotic wounds are the exception. Lesions with significant tissue damage generally heal within about 45 days. If the bite happened in an area with more fatty tissue, like the thigh or buttocks, healing can take dramatically longer, potentially up to three years in extreme cases. These severe bites often leave a permanent scar.
Black Widow Bite Recovery
Black widow bites cause a different kind of problem. The bite mark itself is small and may barely be visible, but the venom triggers bodywide symptoms: muscle pain and spasms, sometimes spreading to the back, chest, or abdomen. In moderate cases, you’ll also experience sweating near the bite site. Severe bites can cause nausea, vomiting, headache, and a racing heart.
The pain peaks around three hours after the bite and symptoms generally worsen for up to 12 hours. After that, they start to subside. Most people find the pain clears up within a few days, though severe cases can linger longer. The bite wound on the skin itself heals similarly to other minor punctures, usually within a week or so, but the muscle pain is what makes black widow bites miserable.
What Normal Healing Looks Like
Knowing what’s normal helps you spot what isn’t. Any spider bite will cause some redness, mild swelling, and tenderness for the first couple of days. That inflammation is your body doing its job. By day three or four, the redness should be shrinking, not growing. By the end of the week, most bites are just a fading mark.
Your body repairs the wound in overlapping stages. After the initial inflammatory cleanup (the first several days), new tissue starts filling in, a process that can continue for up to four weeks in deeper wounds. Even after the surface looks healed, the skin underneath continues remodeling for months, which is why bite scars can fade over time.
Signs of Infection
The real risk with most spider bites isn’t the venom. It’s infection. Scratching an itchy bite introduces bacteria, and the broken skin gives them an entry point. Cellulitis, a spreading skin infection, is the most common complication.
Watch for these warning signs:
- Expanding redness that pushes beyond the original bite area, especially red streaks radiating outward
- Increasing warmth and swelling around the bite after the first two days, when it should be improving
- Fever, chills, or swollen lymph nodes developing days after the bite
- Pus or yellow drainage from the bite site, or blisters forming around it
If redness, swelling, or blisters are expanding beyond the original border of the bite, that’s a sign to get medical attention promptly. An infected bite that would have healed in a week can turn into a problem that takes weeks of antibiotics to resolve.
What Helps (and What Might Not)
For a standard spider bite, keeping it clean is the single most useful thing you can do. Wash with soap and water, avoid scratching, and leave it alone. Over-the-counter pain relievers can take the edge off, and hydrocortisone cream helps with itching and inflammation. Antihistamines can reduce significant swelling.
Ice is commonly recommended, and it does numb pain in the short term. But the evidence behind the full rest-ice-compression-elevation approach is surprisingly thin. The doctor who originally popularized it later walked back the recommendation, acknowledging it wasn’t well supported by clinical data. Some providers now suggest that aggressively reducing inflammation with ice may actually slow healing by interrupting your body’s natural repair process. A brief application to manage pain is reasonable, but icing a bite repeatedly for days isn’t clearly beneficial.
For brown recluse bites that develop open wounds, healing depends on keeping the wound clean and protected. Larger necrotic wounds sometimes need medical debridement (removal of dead tissue) to heal properly, and deep tissue loss in fatty areas may eventually require skin grafting. These are the rare worst-case scenarios, not the norm.
Quick Reference by Bite Type
- Common house spiders: 5 to 7 days, no treatment needed beyond basic wound care
- Brown recluse (mild): about 3 weeks to full healing
- Brown recluse (severe/necrotic): 45 days on average, up to months or years for deep tissue wounds
- Black widow (symptoms): peak at 3 to 12 hours, pain resolves within a few days
- Any bite with secondary infection: adds 1 to 3 weeks depending on severity and treatment