Learn About Bug Bites That Cause Bruising and How to Treat Them

Understanding Bug Bites That Cause Bruises

It's every outdoor enthusiast's worst nightmare - you wake up with an itchy, swollen welt that has turned into a dark bruise. Bug bites can definitely cause bruising, but not all bug bites result in this type of reaction. By learning to identify the different types of bites and stings, you can get the proper treatment and find relief from the symptoms.

What Causes Bruising from Bug Bites?

Bruising is caused by ruptured blood vessels leaking blood into the surrounding tissues. Bug bites can damage small capillaries in the skin, allowing blood to pool and create a bruise. The venom or saliva from some insects also contains molecules that can prevent blood from clotting properly, making bruises more likely.

Bites that cause bruises are often more painful and swollen than a normal bug bite. The area may throb or ache. Bruises usually take a day or two to fully develop and can stick around for up to two weeks as the body reabsorbs the blood.

Signs of an Infected Bruising Bug Bite

While most bug bite bruises heal without issue, they can become infected. Signs of an infected bruise from a bug bite include:

• Expanding redness around the bite
• Pus or yellow/green discharge
• Worsening pain and swelling
• Red streaks spreading from the bite
• Flu-like symptoms like fever and chills

See a doctor right away if your bite shows signs of infection. You may need antibiotics to clear it up.

Bug Bites That Commonly Cause Bruises

Now let's go over some of the main bug culprits for bruising bites:

1. Spider Bites

While the majority of spider bites cause red, swollen bumps, some spiders can cause bruising. The venom from a black widow or brown recluse spider prevents blood from clotting properly. This results in pooling around the bite site.

Black widow bites cause painful cramping before the venom causes a target-shaped bruise. Brown recluse spiders leave a swollen blistery lesion that turns dark purple, black, or blue.

2. Bed Bug Bites

Bed bugs feed on human blood, leaving behind clusters of extremely itchy bites. These pests tend to bite exposed areas of skin which can develop bruises after scratching, like the arms, neck, or ankles.

The bruises appear as small red dots or larger patches of mottled red skin. Use an anti-itch cream and keep the bites covered to prevent bruising from scratching.

3. Horsefly Bites

Horseflies and deerflies bite humans while feeding on blood. They make a tearing-cutting motion to access blood vessels, which can cause bleeding under the skin. Bites often swell dramatically and turn into large, painful bruises.

Apply ice and take an antihistamine to reduce swelling. See a doctor for bites that become infected.

4. Mosquito Bites

Though not common, some people can develop bruises from mosquito bites. This reaction is the result of an allergy to mosquito saliva. The immune system releases histamine, causing fluid leakage and burst blood vessels.

Avoid scratching, which can make bruising worse. Use hydrocortisone cream and antihistamines to reduce swelling and itching.

Other Causes of Bug Bite Bruises

Here are some other bug bites that may occasionally cause bruised skin:

• Bee, wasp, hornet, and ant stings
• Flea bites
• Kissing bug bites
• Wheel bug bites
• Stink bug bites

The venom or saliva from these insects can trigger an allergic reaction with swelling, fluid buildup, and ruptured capillaries. Some also have anticoagulant properties. Seek emergency care for any bite or sting that causes severe bruising, muscle weakness, or difficulty breathing.

First Aid for Bruising Bug Bites

Follow these tips to care for a bug bite with a bruise:

• Wash the area with soap and water to remove any venom/saliva and decrease infection risk.
• Apply a cold compress or ice pack to reduce pain, swelling, and inflammation.
• Keep the area elevated above heart level when possible.
• Use OTC hydrocortisone cream to ease itching and swelling.
• Take antihistamines like Benadryl to reduce swelling and itching.
• Avoid scratching or picking at the bite as this can worsen bruising.
• See a doctor for severe bruising or signs of infection like pus.

When to Seek Medical Care for a Bruising Bug Bite

While most bug bite bruises can be safely treated at home, see a doctor in these situations:

• The bite is from a spider, tick, or scorpion.
• You develop any signs of infection like pus, red streaks, or fever.
• The bite does not respond to home treatment after 2-3 days.
• The bite is located on the face, throat, or genitals.
• The bruise enlarges or becomes more painful.
• You have a history of allergic reactions to insect bites.
• You were bitten multiple times.

Severe spider bites like a black widow may require antivenom. Infected bites need prescription antibiotics. Your doctor can provide stronger anti-itch and antihistamine medications as well.

Preventing Bruising Bug Bites

You can take steps to avoid bug bites that cause bruising:

• Apply insect repellent containing DEET, picaridin, or oil of lemon eucalyptus when going outdoors.
• Wear long sleeves and pants in wooded, grassy areas.
• Tuck pants into socks when in tick habitat.
• Avoid areas with beehives, wasp nests, etc.
• Keep skin covered and use permethrin on clothes and camping gear.
• Stay away from standing water where mosquitoes breed.
• Use bed bug mattress encasements and monitor for signs of infestation.
• Seal cracks around the home to prevent entry of spiders, stink bugs, etc.

Check yourself thoroughly for ticks after being in wooded or high grass areas. Remove any ticks promptly with tweezers. Also shower after spending time outdoors to wash away loose insects.

When to Worry About a Bruising Bug Bite

Most bruised bug bites will heal without issue, but some require prompt medical treatment. Seek emergency care if you experience:

• Difficulty breathing or swallowing
• Swelling in the throat or tongue
• Dizziness, chest pain, or palpitations
• Widespread hives or itching
• Slurred speech or confusion
• Joint pain or muscle weakness

These can signal a severe allergic reaction that needs epinephrine and other treatments. Call 911 if you or someone else has a severe reaction to an insect bite or sting.

The Takeaway

Bug bites often cause red, swollen bumps but some can also lead to bruising. The venom or saliva from certain insects promotes bruising by damaging blood vessels and preventing clotting. While painful and unpleasant, most bite-related bruises can be managed at home. However, seek medical care for severe reactions or signs of infection. With proper treatment, bruised bug bites should heal within 1-2 weeks.

Disclaimer: This article is for informational purposes only and does not constitute medical advice. Always consult with a healthcare professional before starting any new treatment regimen.