Most spider bites heal on their own within one to three weeks with basic home care. The key is keeping the bite clean, managing swelling and itch, and watching for the few warning signs that mean you need medical attention. Here’s how to speed up the process and avoid complications.
First Aid in the First Few Hours
Start by washing the bite area thoroughly with soap and water. This is the single most important step, because the biggest risk from most spider bites isn’t venom but secondary infection from bacteria on the skin or the spider’s fangs.
After cleaning, apply an ice pack or cold wet compress to the bite. Use a cloth barrier between the ice and your skin, and apply it in 10- to 15-minute intervals. Cold reduces swelling, slows the spread of any venom in the tissue, and dulls the pain. If the bite is on an arm or leg, keep the limb elevated when you can. This helps fluid drain away from the area and limits swelling.
Managing Pain, Swelling, and Itch
For pain that lingers after the first few hours, ibuprofen or acetaminophen both work well. If itching is the bigger problem, an oral antihistamine like diphenhydramine (Benadryl) or cetirizine (Zyrtec) can take the edge off. These are more effective than topical anti-itch creams for bug bites because the irritation sits below the skin’s surface.
Avoid scratching the bite. Broken skin invites bacteria, and infection is the most common reason a minor bite turns into a bigger problem. If the area feels unbearably itchy, a cool compress often provides more relief than scratching would.
Skip the Home Remedies
Baking soda paste, lemon juice, salt, and activated charcoal are all commonly recommended online for spider bites. None of them work. The logic behind these remedies is that they can draw out or neutralize venom, but venom gets absorbed into tiny blood vessels beneath the skin within seconds. By the time you mix up a paste, there’s nothing left at the surface to draw out. Cleveland Clinic physicians have confirmed there’s no proven evidence that any of these approaches affect healing.
What Normal Healing Looks Like
A typical spider bite follows a predictable path. You’ll see redness, mild swelling, and some tenderness for the first day or two. The swelling peaks around 24 to 48 hours, then gradually fades. Most bites from common house spiders are fully healed within one to two weeks without any treatment beyond basic first aid.
Brown recluse bites are the main exception. If the spider injected only a small amount of venom, discomfort usually disappears within three to five days. In more severe cases, an ulcer forms at the bite site, the surrounding skin breaks down over one to two weeks, and the resulting wound can take several months to close completely. The majority of brown recluse bites, though, heal within three weeks.
It Might Not Be a Spider Bite
This is worth knowing: many skin lesions blamed on spiders are actually staph infections, including MRSA. Research published in American Family Physician found that a large number of patients who show up saying they have a spider bite actually have community-acquired MRSA. A reliable spider bite diagnosis requires that someone actually saw the spider bite them. If you didn’t, and the wound is getting worse, consider that it could be a bacterial infection that needs antibiotics rather than a bite that needs time.
A staph infection and a spider bite can look nearly identical in the early stages: a red, swollen, painful bump that may develop a central area of pus or dead tissue. The difference matters because a staph infection won’t resolve on its own and can spread quickly without proper treatment.
Warning Signs That Need Medical Attention
Most spider bites are harmless and just need patience. But get medical care right away if you notice any of these:
- Spreading redness or red streaks extending outward from the bite, which suggests infection is moving through nearby tissue
- A growing wound at the bite site, especially one that develops a dark or purple center
- Severe pain or abdominal cramping, which can signal a black widow bite even when the bite itself looks minor
- Difficulty breathing or swallowing, which indicates a systemic reaction to venom
- You know or suspect the spider was a black widow or brown recluse
Black widow bites can cause intense muscle cramping, nausea, and changes in heart rate that develop over several hours. The bite mark itself is often tiny and easy to overlook. Antivenom exists for black widow bites and is used in hospital settings when symptoms are severe.
For brown recluse bites that develop into open wounds, treatment focuses on keeping the wound clean, splinting and elevating the area, and treating any bacterial infection that develops on top of the wound. Some severe cases eventually need skin grafting, but that’s uncommon.
Tetanus and Infection Prevention
Spider bites carry an increased risk for tetanus. If you’re not up to date on your tetanus immunization, a booster is recommended after a significant bite. Most adults need a tetanus booster every 10 years, so if you’re unsure of your status, it’s worth checking.
To prevent infection during healing, keep the bite covered with a clean bandage, wash it gently once or twice a day, and resist the urge to pop or squeeze any blister that forms. A blister is your body’s natural bandage, and breaking it creates an entry point for bacteria.