Most spider bites can be treated at home with basic first aid: clean the wound, apply ice, and take an over-the-counter pain reliever. The vast majority of spider bites cause only mild, localized reactions that resolve within a few days. Bites from black widows, brown recluses, or hobo spiders are the exception and can require medical attention.
First Aid for Any Spider Bite
Start by washing the bite with mild soap and water. This is the single most important step, since the real risk from most bites isn’t venom but secondary infection from bacteria on the skin or the spider’s fangs.
After cleaning, apply a cool, damp cloth or a cloth-wrapped ice pack to the area for 15 minutes each hour. This helps reduce swelling and dulls the pain. If the bite is on your hand, arm, foot, or leg, keep that limb elevated when you can. Elevation slows the spread of swelling and makes the first day or two more comfortable.
For pain, take whatever over-the-counter pain reliever you normally use, such as ibuprofen or acetaminophen. If the area is itchy, an antihistamine like diphenhydramine (Benadryl) or cetirizine (Zyrtec) can help. Follow the dosing instructions on the package.
How to Tell if a Bite Is Infected
A normal spider bite will be red, slightly swollen, and maybe itchy for a few days. An infection looks different. Watch for increasing pain (not just itch), expanding redness that feels warm or hot to the touch, fever, or yellow or greenish discharge from the wound. These signs often point to cellulitis, a bacterial skin infection that needs antibiotics.
One useful distinction: insect and spider bites typically itch more than they hurt, and redness stays close to the bite. Cellulitis is tender and painful, and the redness spreads outward over hours. Many skin infections, including MRSA, are mistakenly blamed on spider bites because they start as a red, swollen bump. If a “bite” you never saw happen keeps getting worse after 48 hours, it’s worth having a doctor look at it, since it may not be a bite at all.
Tetanus and Puncture Wounds
Spider bites are puncture wounds, and the CDC classifies puncture wounds as “dirty or major” for tetanus purposes. If your last tetanus shot was five or more years ago, you may need a booster. This is especially worth checking if you were bitten outdoors or in a shed, garage, or other dusty environment where tetanus-causing bacteria thrive.
Black Widow Bites
Black widow venom is a neurotoxin, meaning it targets the nervous system rather than the skin. The bite itself may feel like a pinprick and look unremarkable, but within 30 to 60 minutes you can develop intense muscle pain and cramping, often starting near the bite and spreading to the abdomen, back, or chest. Other symptoms include a severe headache, nausea and vomiting, a racing pulse, and high blood pressure.
Children under 16 and adults over 60 are at the highest risk and may need hospitalization for breathing problems, heart issues, or uncontrollable muscle pain. Treatment in the hospital focuses on controlling pain. Doctors typically use a combination of standard pain relievers and sometimes stronger medications like opioids or blood-pressure-lowering drugs. Antivenom exists but is no longer the first-line treatment in most protocols. Current guidelines recommend trying pain management first for one to two hours, with antivenom reserved for cases where pain relief isn’t working.
If you suspect a black widow bite, don’t wait for symptoms to escalate. Head to an emergency room, especially if the person bitten is a child or an older adult.
Brown Recluse Bites
Brown recluse venom works differently. It destroys skin tissue. The bite often starts painlessly and looks like an ordinary red mark. Over the next several hours to days, the center of the bite may darken, blister, and eventually form an open sore as the tissue dies. A ring of pale skin surrounded by a red, inflamed border (sometimes described as a “bull’s-eye” pattern) is a hallmark sign.
Most brown recluse bites remain small and heal on their own within a few weeks, but a minority progress into larger wounds that take months to close. Medical treatment for more severe bites involves specialized wound care. In clinical settings, doctors have used enzyme-based ointments on the dead tissue and anti-inflammatory creams on the surrounding skin, applied daily until the wound heals. Surgical removal of dead tissue is sometimes necessary for larger wounds, but doctors generally wait weeks before considering this to let the boundaries of the damaged area become clear first.
If a bite develops a dark or blistered center, or if you notice the wound growing rather than shrinking after a few days, have it evaluated. Early medical management reduces the chance of scarring and complications.
Symptoms That Need Emergency Care
Regardless of which spider bit you, certain symptoms signal a systemic reaction that needs immediate attention:
- Difficulty breathing or tightness in the chest
- Heart palpitations or a racing pulse
- Severe muscle pain, cramps, weakness, or paralysis
- Nausea and vomiting
- Vision problems or a severe headache
- Signs of infection, including fever or discharge from the wound
Most people who develop these symptoms never actually saw the spider that bit them. You don’t need to identify the spider to get treated. If you do happen to find it (even if it’s dead), bring it with you. But don’t delay care to go searching.
What Most Bites Actually Look Like
The overwhelming majority of spider bites come from species whose venom causes nothing more than a red, itchy bump similar to a mosquito bite. It shows up within a few hours, peaks in swelling around day one or two, and fades within a week. You can manage it entirely at home with the soap-water-ice-elevation approach and an antihistamine for itch.
If you’re dealing with a bite that fits this profile, the most helpful thing you can do is leave it alone. Resist the urge to squeeze or scratch it. Keep it clean, apply a simple bandage if your clothing rubs against it, and let your body handle the rest.