Skin Abscess and Boils: What Causes Them, Why Squeezing Doesn't Help, When Drainage Is Needed and When Antibiotics Are Enough
An abscess (skin abscess) is a pocket of pus caused by a bacterial infection in or under the skin, producing a swollen, red, warm and painful lump. The most common type is a single-headed boil from a hair follicle (furuncle or boil). A small abscess may burst and heal on its own within 1–3 weeks, while a soft lump 1–2 cm or larger usually needs a doctor to drain it, because medicine alone cannot reach the pus pocket well enough. Do not squeeze or pierce an abscess yourself, wherever it is.
What patients call an "abscess" covers several kinds of lumps that are treated differently. Some are inflamed cysts and some are chronic sweat gland disease. This article therefore separates abscesses by type and location, and explains what a headless abscess is, what to do when an abscess bursts, how drainage is done, which medicines are used, and how many days it takes to heal.
What does an abscess look like?
Features that suggest an abscess include the following.
Starts as a hard, red, painful lump: In the first 1–3 days the lump is usually firm and tender, and no pus is visible yet.
Gradually softens in the middle: When pus collects into a pocket, pressing the lump feels like there is fluid inside. Doctors call this fluctuation.
Warm and throbbing: The pain keeps increasing until the pus drains, because pressure inside the pocket rises.
May or may not have a head: A shallow abscess often shows a whitish-yellow pus spot in the center. A deep abscess may have no head at all.
Varied size: From under 1 cm to several centimeters.
Often appears where there is hair and friction: The face, neck, armpits, buttocks, thighs and groin.
What causes an abscess?
Most abscesses are caused by the bacterium Staphylococcus aureus, including a drug-resistant strain called MRSA. This bacterium lives on the skin and in the nose of many people without causing disease; about 20–30% of people carry it in the nose. When it enters the skin through a hair follicle, a wound or a blocked gland, the body sends white blood cells to surround it and builds a wall around it. Pus is a mixture of white blood cells, bacteria and dead tissue.
Factors that make abscesses more likely include:
Folliculitis or ingrown hairs that spread deeper
Shaving or plucking hair, friction from tight clothes, and sweat in skin folds
Picking at acne or wounds, or scratching skin with existing dermatitis
Diabetes, weakened immunity, immunosuppressive drugs and excess body weight
Sharing towels or razors with someone who has an abscess or carries the bacteria
Single-headed abscess (furuncle): a lump from a hair follicle
Appearance: A red, painful lump about 1–2 cm across with a hair follicle at the center, usually with a single pus head. Common on the neck, face, armpits, buttocks and thighs.
Cause: Staphylococcus aureus spreads from the hair follicle into the surrounding tissue. It is deeper than ordinary folliculitis, which is a shallow bump under 5 mm.
Severity/urgency: Mostly not dangerous in healthy people. A small lump may burst and shrink on its own within 1–3 weeks, but it can be quite painful in the meantime.
When to see a doctor: A soft lump 1–2 cm or larger, no improvement after 3–5 days of warm compresses, pain bad enough to disturb sleep, or any of the warning signs listed below.
Carbuncle: a large lump with several heads
Appearance: A large lump with several pus heads, formed from several hair follicles joined together. Common on the back of the neck and the back.
Cause: The same infection as a single-headed abscess but spreading wider. It is more common in people with diabetes.
Severity/urgency: More severe than a single-headed abscess, often with fever and tiredness.
When to see a doctor: Every case should see a doctor. Details and treatment are in the article Carbuncle: why you shouldn't squeeze it and how to drain it safely
Headless abscess: a painful lump with no visible pus
Appearance: A firm or springy, red and painful lump with no pus spot visible. The skin on top may look tight and shiny. Many people wait several days for it to form a head.
Cause: There are several possibilities. The first is an early abscess where the pus has not yet collected. The second is a deep abscess where the pus lies under the skin and never forms a head. The third is another lump that looks similar, such as an inflamed cyst, chronic sweat gland disease (hidradenitis suppurativa), or inflamed lymph nodes in the armpit, groin or neck.
Severity/urgency: No head does not mean not serious. A deep abscess may hold more pus than you can see. Poking a needle in to look for pus risks spreading the infection and injuring the tissue underneath.
When to see a doctor: The lump has not shrunk within 3–5 days of warm compresses, it is growing fast, or there is fever. The doctor will feel the lump and may use ultrasound to see whether there is a pus pocket, which decides whether drainage is needed. A hard lump that is not painful and grows slowly is a different matter from an abscess and should also be examined by a doctor.
Abscess on the face: do not squeeze the central triangle of the face
Appearance: A painful lump on the nose, upper lip, cheek crease or around the eye. It can swell a lot relative to its size because the facial skin has a rich blood supply.
Cause: Often starts as folliculitis inside the nose, nose picking, or squeezing a pimple.
Severity/urgency: The area from the corners of the mouth up to the bridge of the nose is known as the danger triangle. Veins here connect to the venous sinus behind the eye socket, and squeezing may push bacteria in. Infected clotting in this sinus (cavernous sinus thrombosis) is very rare but life-threatening.
When to see a doctor: See a doctor within 24 hours if the abscess is in the middle of the face or around the eye, and go to the emergency room immediately if the eye swells shut, there is eye pain, double vision, severe headache or high fever. Facial abscesses are often treated with antibiotics as well, and the doctor will consider drainage suited to the location.
Abscess in the armpit, groin and under the breast: tell it apart from HS
Appearance: Painful lumps in skin folds. If it happens once and heals completely, it is usually an ordinary abscess. If lumps keep coming back in the same place, with tunnels or connected channels, long-standing pus discharge and thick band-like scars, think of chronic sweat gland disease (hidradenitis suppurativa or HS).
Cause: An ordinary abscess comes from a hair follicle infection, while HS starts from blockage and long-term inflammation of the hair follicles. Bacteria are only one part of the problem, so draining the pus case by case does not stop it.
Severity/urgency: A single abscess is cured with treatment. HS is a chronic disease that, if left alone, forms tunnels under the skin and tight scars. The criterion used to suspect it is at least 2 recurrences in 6 months at the usual location.
When to see a doctor: Lumps that keep coming back in the armpit, groin or under the breast should see a dermatologist to confirm the diagnosis and plan long-term care. Read more at Hidradenitis suppurativa (HS). A painful breast lump while breastfeeding, or a groin lump after a risk of a sexually transmitted infection, should see a doctor soon because the treatment is different.
Abscess on the buttocks and around the anus
Appearance: A lump on the buttock cheek is usually an ordinary follicle abscess, but a lump right next to the anal opening with throbbing pain, pain when sitting or passing stool, may be a perianal abscess. A lump at the top of the buttock crease may be a pilonidal abscess.
Cause: A perianal abscess usually starts from an infected gland inside the anus, not from the skin. A pilonidal abscess comes from hairs embedded in the buttock crease.
Severity/urgency: A perianal abscess does not resolve with warm compresses alone. If left, it may spread or form a fistula to the anus. A fast-spreading infection of the perineum is an emergency, especially in people with diabetes.
When to see a doctor: A lump next to the anus should see a doctor within 24 hours and usually needs drainage by a surgeon. If the skin there turns dark purple or there is severe pain with fever, go to the emergency room immediately.
Inflamed cysts that people call abscesses
Appearance: A round lump under the skin that has been there a long time without pain and suddenly becomes swollen, red and painful like an abscess. A small dark opening is often seen in the center. What comes out is smelly and cheese-like, grayish white.
Cause: An epidermoid cyst sac ruptures or leaks under the skin, so the body becomes inflamed in response to the sac contents. Often this is not mainly an infection, so antibiotics help little.
Severity/urgency: Not dangerous, but if part of the cyst wall remains it will come back in the same place. Draining the pus relieves the pain but does not remove the sac.
When to see a doctor: When the lump is inflamed and painful. The doctor may drain it or inject anti-inflammatory medicine into it, then schedule surgery to remove the whole sac after the inflammation settles, usually after about 4–6 weeks. How to tell these lumps apart is covered in Fatty lumps under the skin and cysts
Abscess in children
Appearance: A red, painful lump similar to adults. Common on the buttocks, diaper area, legs and scalp. Young children cannot say what hurts, so they may cry, fuss, or not let anyone touch the spot.
Cause: Bacteria enter through scratches or tiny wounds such as diaper rash, mosquito bites or eczema, and spread within the home or school through contact and shared towels.
Severity/urgency: Babies under 3 months are high risk because their immune system is not yet ready and symptoms may be unclear. Children's medicines are calculated by body weight, and some adult medicines are not suitable for children.
When to see a doctor: A baby under 3 months with a lump or a fever of 38°C or higher should see a doctor the same day. Older children should see a doctor if the lump grows fast, or there is fever, drowsiness or recurrence. A child who has had repeated abscesses since the first years of life should have their immune system assessed.
Abscess in people with diabetes
Appearance: Looks like an ordinary abscess, but may hurt less than expected if nerve endings are damaged. An abscess on the foot may go unnoticed until it is very swollen.
Cause: High blood sugar makes white blood cells work less well, and poor circulation slows healing. Repeated abscesses in someone who has never been tested may be the first clue to diabetes.
Severity/urgency: Higher risk than the general population. The infection spreads quickly and can reach the bloodstream. An abscess on the foot or perineum needs special care.
When to see a doctor: See a doctor within 24 hours every time there is an abscess, and do not wait and watch at home. The doctor usually also checks blood sugar and HbA1c, and blood sugar control is part of the treatment. Take care that warm compresses do not scald the feet if they are numb.
Why do abscesses keep coming back?
Appearance: Two to three or more abscesses in a year. They may appear in different places, or others in the household may have them too.
Cause: The causes doctors look for are as follows.
Carrying the bacteria: Staphylococcus aureus in the nose, armpits or groin, which then reinfects your own skin.
Drug-resistant MRSA: Medicines used before may not cover it, so the pus should be cultured.
Not an abscess in the first place: For example HS, a cyst whose sac is still there, or a pilonidal sinus at the buttocks.
Incomplete drainage or a foreign body left behind: For example hair fragments, thorns or splinters.
Underlying conditions: Diabetes, weakened immunity, immunosuppressive drugs, kidney failure, and rare white blood cell disorders.
Behavior and environment: Repeated shaving, tight clothes, shared towels, or household members who carry the bacteria.
Severity/urgency: Not urgent if there is no fever or spreading lump, but it should not be treated one episode at a time without looking for the cause.
When to see a doctor: See a doctor at the second or third episode, going while the lump is still there so the pus can be cultured. The doctor may consider decolonization: 2% mupirocin ointment in the nostrils twice a day for 5 days, together with bathing in 2–4% chlorhexidine once a day for 5–14 days, taking care to keep it out of the eyes and ears, and washing towels and bedding separately. This lowers the chance of recurrence in some people, but the bacteria can return, especially if household members still carry them.
How is an abscess different from inflamed acne, folliculitis and cellulitis?
There are many kinds of swollen, painful skin lesions, and telling them apart correctly lets the right treatment be chosen.
Deep inflamed acne (nodulocystic acne): Appears in many spots on the face, chest and back together with other types of acne. Treated mainly with acne medicine, not drainage.
Folliculitis: Many small bumps along hair follicles, under 5 mm, shallower than an abscess, with no deep pus pocket.
Cellulitis: A widely spreading red, warm rash with unclear borders and no pus lump to drain. Treated with antibiotics. Read more at Cellulitis, which can occur together with an abscess.
Inflamed cyst: The lump was there before, and an opening is often visible in the center.
Lymphadenitis (inflamed lymph node): A round lump in the neck, armpit or groin, often with an infection elsewhere that came first.
Why you shouldn't squeeze or pierce an abscess yourself
Squeezing lets some pus out and brings temporary relief, but it has several drawbacks.
An abscess has a wall around the pocket and sometimes several compartments. Pressure from outside cannot drain it fully, so the pus left behind builds up again.
The pressure from squeezing may push bacteria into the surrounding tissue and the bloodstream.
Hands and needles are not sterile, which leads to re-infection and more scarring.
An abscess in the middle of the face carries the specific risks explained above.
For the same reason, do not use needles, knives, sharp objects or folk-remedy poultices to make it burst faster.
Self-care for an abscess that actually works
Home care suits a small abscess under 1 cm with no warning signs that is not in the middle of the face.
Wash your hands, then apply a clean cloth soaked in warm water for 10–15 minutes at a time, 3–4 times a day. The heat increases blood flow and helps the pus collect.
Wash the area 1–2 times a day with clean water and soap, and pat gently dry with a clean cloth.
Cover with gauze if pus is seeping or the spot is being rubbed.
For pain, use paracetamol 500–1,000 mg every 4–6 hours as needed, no more than 4,000 mg a day. If you have liver disease or drink alcohol regularly, consult a doctor first.
Use a separate towel, wash anything that touched the abscess, and wash your hands after every touch.
Do not buy antibiotics to take on your own, because they may not match the bacteria, do not help a pus pocket that already exists, and can cause drug resistance. Antibiotic creams do not reach into the pus pocket either. If the lump has not shrunk after 3–5 days of care, or the pain and swelling increase, see a doctor.
What to do when an abscess bursts
When an abscess bursts by itself, the pain usually drops right away because the pressure in the pocket is gone. What you should do is help the pus drain cleanly; you do not need to squeeze it all out.
Wash your hands, then wash the area with clean water and mild soap, or with normal saline wound wash.
Gently blot the draining pus with clean gauze. Do not squeeze or poke into the opening.
Cover with clean gauze, changing it 2–3 times a day or when it is soaked through.
You can keep applying warm compresses with a fresh clean cloth so the remaining pus drains out.
You do not need to wash the wound repeatedly with alcohol or hydrogen peroxide, because they irritate tissue that is repairing itself, and do not put toothpaste or herbs on the wound.
See a doctor if, 2–3 days after bursting, there is still a lot of pus, the lump is still hard, the redness is spreading, there is fever, or the abscess is in the middle of the face. A burst abscess does not mean it has drained completely; in some people a pocket remains, and the doctor will open and clean it.
How is an abscess drained?
Incision and drainage is the main treatment for an abscess with a pus pocket. It is mostly a short procedure done without a hospital stay. The usual steps are as follows.
Examination first: Feel for the pus pocket. Ultrasound may be used if the lump is deep or the diagnosis is uncertain.
Cleaning and local anesthetic: Lidocaine local anesthetic is injected around the lump. Inflamed tissue may not go fully numb, so you may feel some pain; tell the doctor so more can be given.
Making a small opening: A cut is made along the skin over the spot where the pus is closest to the surface, so the pus can come out.
Draining and washing: The dividing walls inside the pocket are broken up so all the pus comes out, then it is rinsed with saline.
Sending pus for culture when indicated: For example with recurrence, no response to medicine, or weakened immunity. Results take about 2–3 days.
Wound care afterward: Usually the wound is not stitched closed, so it heals from the inside out. A large pocket may be packed with gauze or have a drain placed.
All of this usually takes about 15–30 minutes. After the procedure, pain usually improves clearly within 24–48 hours. The doctor usually schedules a wound check within 1–2 days, and in between you should dress the wound as advised. Abscesses in some locations, such as around the anus, hand, breast, or very deep abscesses, may need referral to a surgeon. What decides the result most is whether the pus is drained completely; if a pocket remains, it can come back.
Antibiotics for abscess: when and which ones
A small abscess in a healthy person that drains well may not need medicine at all. A large study of uncomplicated abscesses found that giving antibiotics after drainage raised the cure rate from about 70–75% to about 80%, so the benefit exists but is modest. Doctors therefore decide according to each person's risk.
Indications where antibiotics are often given: Fever or whole-body symptoms, redness spreading around the lump, an abscess larger than 5 cm, multiple abscesses, locations that are hard to drain or risky such as the face, hands and genitals, diabetes or weakened immunity, very young or elderly patients, and an abscess that does not improve after drainage.
Medicines commonly used in adults when the bacteria are ordinary and not drug-resistant
Cephalexin (cephalexin) by mouth 500 mg four times a day for 5–7 days
Dicloxacillin (dicloxacillin) by mouth 500 mg four times a day on an empty stomach for 5–7 days
Medicines used when culture finds or MRSA is suspected
Trimethoprim-sulfamethoxazole (trimethoprim-sulfamethoxazole) 160/800 mg, 1–2 tablets twice a day. Do not use if allergic to sulfa drugs
Doxycycline (doxycycline) 100 mg twice a day. Not used in pregnant women and young children
Clindamycin (clindamycin) 300–450 mg three times a day. Watch for severe diarrhea
The usual duration is 5–7 days, and may be extended up to 10 days depending on the response. What decides whether the medicine works is that the pus is drained completely and the bacteria are sensitive to that medicine. Symptoms should improve within 48–72 hours. If not, the doctor will check whether a pus pocket remains or the bacteria are resistant. If pus is still trapped in a pocket, medicine alone is usually not enough, but an early inflamed lump with no pus pocket yet may respond to medicine together with warm compresses.
People who receive medicine should take it until finished as the doctor prescribed, and tell the doctor about any drug allergies, pregnancy and underlying conditions every time. The choice and dose of medicine are the decision of the examining doctor. The information above is meant to help you understand the approach, not to buy medicine and use it yourself.
How many days does an abscess take to heal?
The time depends on the size and the treatment. A rough timeline in a healthy person is as follows.
Small abscess cared for at home that bursts or shrinks: About 1–3 weeks.
After drainage: Pain drops within 24–48 hours, pus decreases within 2–3 days, a small wound closes within 1–2 weeks, and a deep wound may take 2–3 weeks.
Remaining hard raised lump: It may still be felt for several weeks after the wound closes, then gradually shrinks.
Dark marks or scars: Dark marks may last several months in people with darker skin.
People with diabetes, weakened immunity, or a large multi-pocket abscess usually heal more slowly than this. An abscess that shows no sign of improving within 3–5 days without treatment should see a doctor.
Warning signs that need prompt medical care
See a doctor the same day or go to the emergency room if any one of the following is present.
Fever of 38°C or higher, chills, palpitations or severe tiredness
Redness spreading wider over hours, or red streaks running from the lump along the arm or leg. Draw around the edge of the redness with a pen to track its spread.
The abscess is in the middle of the face, around the eye, nose or upper lip
Diabetes, weakened immunity, taking immunosuppressive drugs, or having chemotherapy
The lump is larger than 5 cm, growing fast, or there are several spots at once
The abscess is on the hand, a finger, around the anus or on the genitals
Severe pain out of proportion to the lump, skin turning dark purple, blisters or numbness, which may be a deep infection (necrotizing infection) needing emergency treatment
A baby under 3 months
How to prevent abscesses
Wash small wounds with clean water and soap, then cover them until healed
Do not pick at acne or ingrown hairs, or scratch the skin until it is broken
Do not share towels, razors or sports kit, and wash your hands more often when someone in the household has an abscess
Wear loose clothes and change clothes when you sweat a lot. If abscesses often appear where you shave, stop shaving there for a while
Keep blood sugar controlled if you have diabetes, and treat any existing dermatitis
In brief
An abscess is a pocket of pus from a bacterial infection, most often Staphylococcus aureus
The same kind of swollen, painful lump may be an inflamed cyst, HS, lymphadenitis or cellulitis, which are treated differently
Do not squeeze or pierce it yourself. For a small abscess, use warm compresses for 10–15 minutes, 3–4 times a day
A soft lump 1–2 cm or larger usually needs drainage by a doctor. Medicine alone is not enough
After drainage, pain usually drops within 24–48 hours and the wound closes within 1–3 weeks
Fever, spreading redness, an abscess in the middle of the face, or diabetes are reasons to see a doctor promptly
Frequently asked questions about abscesses
What causes an abscess?
An abscess is caused by a bacterial infection, most often Staphylococcus aureus, which lives on the skin and in the nose of many people. The bacteria enter through a hair follicle, a wound or a blocked gland, and the body builds a wall around them until a pus pocket forms. People who get them more easily include those with diabetes or weakened immunity, frequent friction or hair shaving, and those who pick at acne or wounds. An abscess is not caused only by eating certain foods or by being unclean.
How is an abscess treated? What needs to be done?
Treatment depends on the size and location. A small abscess under 1 cm in a healthy person starts with warm compresses for 10–15 minutes, 3–4 times a day. A soft lump of 1–2 cm or larger usually needs a doctor to drain the pus under local anesthetic. Antibiotics are added when indicated, such as fever, spreading redness, diabetes or a facial abscess, with the doctor choosing the medicine and duration, usually 5–7 days.
What can I do to treat an abscess myself?
At home you can apply warm compresses with a clean cloth for 10–15 minutes, 3–4 times a day, wash with clean water and soap, cover with gauze if pus is seeping, and take paracetamol for pain. What you should not do is squeeze it, pierce it with a needle, apply folk remedies, or buy antibiotics to take on your own. If it has not improved after 3–5 days of care, or the abscess is in the middle of the face, or there is fever, or you have diabetes, see a doctor straight away and do not wait further.
How many days does an abscess take to heal?
A small abscess cared for at home that shrinks or bursts usually heals in about 1–3 weeks. If drained, pain usually drops within 24–48 hours, a small wound closes within 1–2 weeks, and a deep wound may take 2–3 weeks. A small hard lump may still be felt for several more weeks without anything being wrong. People with diabetes or weakened immunity usually heal more slowly. If there is no improvement after 3–5 days, or the pain and swelling increase, see a doctor.
Can an abscess go away on its own?
Some small abscesses go away on their own, especially lumps under 1 cm that burst and drain by themselves and then gradually shrink. But a lump with a larger pus pocket usually does not fully resolve without drainage; it may hurt for a long time, burst and come back, or spread. Waiting and watching is therefore suitable only for a small abscess with no fever, not in the middle of the face, in someone without diabetes. In other cases a doctor should assess it.
What causes an abscess with no head, and what should I do?
A headless abscess may be an early abscess where the pus has not yet collected, or a deep abscess where the pus lies under the skin and does not form a head. Sometimes it is another lump, such as an inflamed cyst or lymphadenitis. Start with warm compresses 3–4 times a day, and do not poke a needle in to look for pus. If after 3–5 days it has not shrunk, is growing fast, or there is fever, a doctor should examine it, possibly using ultrasound to see whether there is a pus pocket.
Related reading: for a large lump with several heads see Carbuncle · for recurring lumps in the armpit and groin see Hidradenitis suppurativa (HS) · for small bumps along hair follicles see Folliculitis · for a round lump under the skin see Fatty lumps and cysts · for a spreading red, warm rash see Cellulitis · for all skin conditions see Skin conditions explained by dermatologists
The information in this article is general knowledge, not a diagnosis or an individual treatment order. Results vary from person to person. Consult a doctor before using any medicine.
Written by Dr. Patara Voravutinon, Dermatologist · Last reviewed November 4, 2026
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