Most spider bites can be treated at home with basic first aid: clean the wound, apply a cool cloth, and take an over-the-counter pain reliever. The vast majority of spider bites are harmless and resolve within days to a few weeks. Only a small number of spider species, primarily widow spiders and brown recluse spiders, cause bites serious enough to need medical attention.
First Aid That Actually Works
Start by washing the bite with mild soap and water, then apply an antibiotic ointment to the area three times a day to help prevent infection. Place a cool, damp cloth or an ice pack wrapped in a towel over the bite for about 15 minutes each hour. This slows swelling and eases pain. If the bite is on an arm or leg, try to keep that limb elevated above your heart or at least in a neutral position.
For pain, both ibuprofen and acetaminophen work equally well. A Cochrane review of oral pain relievers for acute soft tissue injuries found no meaningful difference between NSAIDs like ibuprofen and acetaminophen for pain reduction, so use whichever you tolerate better. An antihistamine can help if the area is itchy.
If your tetanus vaccination isn’t current, it’s worth getting a booster. Spider bites break the skin and can introduce bacteria, so staying up to date on tetanus is a reasonable precaution.
Skip the Baking Soda and Lemon Juice
You’ll find plenty of advice online about applying baking soda paste, lemon juice, salt, or activated charcoal to spider bites. None of these are effective. The idea behind them is that they can somehow draw out or neutralize venom, but venom gets picked up by tiny capillary veins below the skin surface so quickly that it’s gone before anything topical could reach it.
There are two exceptions worth noting. Aloe vera and peppermint oil both provide a cooling sensation on the skin that can feel soothing, though neither treats the bite itself. Think of them as comfort measures, not treatments.
How to Tell If a Bite Is Getting Worse
The tricky thing about spider bites is that early symptoms can look identical to a minor insect bite or even a small skin infection. Normal healing involves some redness, mild swelling, and tenderness that gradually fades over several days. What you’re watching for are signs that things are heading in the wrong direction.
Symptoms that call for immediate medical care include:
- Spreading redness or red streaks radiating outward from the bite, which can signal a bacterial skin infection called cellulitis
- A growing wound at the bite site, especially if the center turns dark or forms an open sore
- Severe abdominal cramping or rigidity, which is a hallmark of widow spider bites and sometimes gets mistaken for appendicitis
- Difficulty breathing or swallowing
- Flu-like symptoms such as fever, chills, nausea, vomiting, tremors, or heavy sweating
- Yellow drainage or blisters forming around the bite
If you’re not sure whether the spider that bit you was dangerous, err on the side of getting checked. You don’t need to bring the spider with you, but noting its size, color, and any markings helps.
Black Widow Bites
Black widow bites are painful immediately and tend to produce symptoms that go well beyond the bite site. Pain and swelling can spread into the abdomen, back, or chest, often accompanied by severe muscle cramping, nausea, vomiting, and sweating. These full-body symptoms are called latrodectism.
Mild to moderate cases are managed with supportive care: pain relief, muscle relaxants, and monitoring. Severe cases may require antivenom, which is available for both black widow and redback spiders. Hospital treatment focuses on controlling muscle spasms and pain until the venom’s effects wear off. Most people recover fully, though the muscle pain and cramping can be intense for 12 to 48 hours.
Brown Recluse Bites
Brown recluse bites behave differently. The initial bite often isn’t very painful, and you may not notice it right away. Over the next several hours to days, the bite area can develop into a painful wound. In some cases, the venom destroys surrounding tissue, creating a necrotic lesion, essentially a patch of dying skin that expands outward.
Cold packs are especially important for brown recluse bites because the venom’s tissue-destroying enzyme is temperature dependent. Keeping the area cool helps slow the damage. Standard first aid applies: clean the wound, elevate the limb, and manage pain with over-the-counter options.
Antibiotics aren’t needed unless a secondary bacterial infection develops. Some older treatments like dapsone have been used but lack strong evidence and carry serious side effects. Steroids may be used in cases where the venom causes red blood cell breakdown, which is a rare but dangerous systemic reaction.
One critical point: don’t let anyone cut into the wound early. Early surgical removal of damaged tissue actually worsens outcomes. If surgery becomes necessary, it should be delayed until the wound edges are clearly defined, typically four to six weeks later. Some patients eventually need skin grafting. With proper care, mild bites resolve within a few weeks, while more severe necrotic wounds can take up to three months to heal fully.
Healing Timeline for Typical Bites
For a common, non-dangerous spider bite, you should see noticeable improvement within a few days. Redness and swelling peak in the first 24 to 48 hours and then gradually fade. Most mild bites are fully healed within one to two weeks.
Brown recluse bites follow a longer arc. Mild cases resolve in several weeks with home care. Bites that develop tissue damage take longer, often healing over the course of two to three months. During that time, the wound may look worse before it looks better, as dead tissue separates from healthy skin. Regular wound cleaning and follow-up with a doctor are important during this period to watch for infection and assess whether surgical repair is needed.
Widow spider bites rarely leave lasting marks on the skin, but the systemic symptoms like muscle pain and fatigue can linger for a week or more after the acute phase passes.