Bed bug bites: what they look like and what to do

In short

• Bed bug bites are itchy raised welts, red or purple, often in a line or a zigzag group of three to five, mostly on skin that was uncovered in bed.
• A bite on its own does not confirm bed bugs. Marks can take from one day to two weeks to appear, and some people never react.
• Most bites heal in a week or two with soap and water, something cold and an anti-itch product from the pharmacy.
• See a clinician for many bites, blisters, signs of infection or an allergic reaction, and call 911 for swelling of the face or throat or trouble breathing.
• Bed bugs are not known to spread disease, and a clean home can have them. Stopping the bites means finding and treating the insects, usually with a pest control company.

What bed bugs are and how you get them

Bed bugs are small insects that feed on blood at night while people sleep. They inject a fluid that numbs the skin, which is why you rarely feel the bite and often wake up with marks you did not notice happening.

They hide in mattress seams, box springs, bed frames, headboards and cracks in nearby furniture or walls, and they usually stay within about 8 feet of where people sleep. Anyone can bring them home: they travel in luggage, bags, clothing, bedding and used furniture.

Frequent travelers and people who share sleeping space with others face a higher risk. Dirt is not the cause, because the CDC states that how clean a place is does not determine whether bed bugs are present.

What the bites look like

• Slightly swollen, itchy welts. They look red on light skin and may look brown, red or purple on dark skin, where redness is harder to see.
• Often in a line or in a zigzag cluster of three to five bites, though they can also be scattered.
• Mostly on the face, neck, arms and hands, the skin that sticks out of the covers.
• Painless when they happen. The marks show up one to several days later, and in some people take up to 14 days.
• Not always visible: some people have no skin reaction at all.

How do you tell them from mosquito or flea bites? Honestly, by the marks alone you often cannot. The CDC says the bites look similar to mosquito or flea bites, and dermatologists note they are also mistaken for hives and other rashes. The useful clues are the pattern, the timing (new marks after nights in one bed) and, above all, physical evidence in the bed.

Blisters, oozing or pus are not part of a plain bite. Treat them as a reason to be examined.

Easing the itch at home

1. Wash.Clean the bites with soap and water. This helps prevent infection and can reduce itching.
2. Cool.Hold an ice pack against the bites to calm swelling and itch.
3. Soothe.If the bites still itch, a nonprescription anti-itch cream such as hydrocortisone, a weak corticosteroid, or an oral antihistamine can help. Follow the package directions and ask a pharmacist if you are unsure, especially for a child.
4. Leave them alone.Scratching can lead to a secondary skin infection, so resist it even when sleep is poor.
5. Fix the bed.Getting rid of the bed bugs is the only way to stop new bites, which is why the next two sections matter as much as any cream.

Without infection or a serious reaction, bites usually heal within a week or two. Bed bugs do not spread disease, but the itching can cost you sleep and some people feel anxious about it.

When to see a doctor

• You have many bites or blisters.
• A bite looks infected: more swollen and painful, hot or red skin around it, or pus or fluid coming out.
• The itch is so bad that you cannot sleep or the bites are getting worse instead of better.
• You have a rash, fever or body aches after being bitten.

Start with your primary care provider or a dermatologist. Tell them about any recent bite or hotel stay so they can weigh the possible causes.

Red flags, call 911 now: swelling of the lips, mouth, tongue or throat; fast or difficult breathing; a tight throat or trouble swallowing; blue, grey or pale skin; sudden confusion, drowsiness or dizziness; fainting. Severe allergic reactions to bed bug bites are rare, but they are an emergency.

How to check a bed or hotel room

1. Park your luggage.In a hotel, put bags in a tiled area such as the bathroom while you inspect, where bugs have fewer places to hide.
2. Start at the bed.With a flashlight, look along mattress seams, the box spring, the bed frame and the headboard, then the bedding.
3. Look for the signs.Rusty or reddish blood spots, tiny blackish dots that look like marker dots, whitish oval eggs about the size of an apple seed, shed skins, live bugs, and sometimes a sweet, musty odor.
4. Widen the search.Check upholstered furniture, dresser drawers, behind wall hangings and loose wallpaper. A bed bug fits in any crack a credit card could slide into.
5. Choose where bags sit.Use the luggage rack, away from the wall. If you find signs, ask for a different room.
6. Check at home.Before unpacking, inspect bags and clothing seams. If you find bugs, wash clothes on high heat and steam the luggage.

Getting rid of an infestation

If you find signs, call a pest control company experienced with bed bugs, or your property manager if you rent. Early detection makes control easier. The EPA warns that treatment can take weeks to months, that everyone in the home has to take part, and that steps may need repeating.

Professionals have access to more intensive and proven methods, including heat treatment of whole houses. Do-it-yourself heating does not work reliably.

• Wash and dry bedding and clothes in a clothes dryer on high heat.
• Seal infested items in bags and vacuum, then close the vacuum bag tightly and put it in an outdoor trash container.
• Cover the mattress and box spring with sealed protective encasements; the bugs trapped inside die.
• Seal cracks and crevices with silicone caulk, and throw out furniture that cannot be cleaned.
• Inspect at least every 7 days and keep watching for a year.

Skip the popular shortcuts. The EPA warns against rubbing alcohol, kerosene and gasoline, which can ignite, against pool or food-grade diatomaceous earth, which can harm your lungs, against sticky traps and against foggers as your only method. Dermatologists add that bug sprays and foggers have little effect. If you do use a pesticide, choose a product registered with the EPA that lists bed bugs on its label and follow the label.

How doctors confirm it and treat the bites

A clinician usually cannot confirm bed bugs from the marks alone, because other bites and rashes look alike. They examine the skin, ask where you sleep and travel, and treat the reaction. The cause is settled by finding a bug or its traces, which is why a bed inspection counts.

A dermatologist may prescribe medicine by class. For itch, that can be a prescription antihistamine or a corticosteroid applied to the bites. For allergic reactions, an antihistamine, a corticosteroid or an epinephrine injection. For infection, an antibiotic, or an antiseptic when it is mild. All of these are used only as prescribed by a doctor.

Questions and answers

Sources

1. CDC — About Bed Bugs
2. American Academy of Dermatology — Bedbugs: Diagnosis and treatment
3. American Academy of Dermatology — How to check for bedbugs
4. American Academy of Dermatology — Tips to prevent and treat bug bites
5. EPA — Do-it-yourself Bed Bug Control
6. NHS — Insect bites and stings

Sources checked on 28 October 2026.