Abscess after an injection: signs, treatment and what not to do

Other names: Абсцесс после укола, постинъекционный абсцесс, шишка после укола, нарыв после инъекции, уплотнение после укола в ягодицу, гнойник после укола, инфильтрат после инъекции

Post-injection abscess is a limited cavity with pus that forms in the soft tissues at the injection site. Most often it occurs after intramuscular injections into the buttock, especially if the drug was injected with a short needle into the subcutaneous tissue, the rules for treating the skin were violated, or many injections were made in the same place. First, a painful compaction is formed - an infiltrate, and at this stage the process is reversible. If an infection occurs, the tissues melt and an abscess forms: the pain becomes throbbing, the skin turns red and hot, and the temperature rises. An abscess can only be treated by opening it up with a surgeon; home heating is dangerous.

🧾 МКБ-10: L02.3 🏥 Where it is treated: 8 First infiltration, then pusIt is strictly forbidden to heatTreatment - autopsy by a surgeon

👨‍⚕️ Which doctor

Surgeon

🔬 Diagnostics

Examination by a surgeon, ultrasound of soft tissues, general blood test

💊 Treatment

Opening and drainage, dressings, antibiotics as indicated

📈 Prognosis

Favorable if opened in a timely manner

⚠️ At risk

Injections in one place, violation of asepsis rules, excess weight, diabetes mellitus, oil solutions

⏱ When to see a doctor

Urgent - examination by a surgeon within 24 hours

🚨 See a doctor urgently

With these signs do not wait for a scheduled appointment — the condition requires emergency care.

Пульсирующая боль и чувство распирания в месте укола
Покраснение и горячая кожа, размягчение в центре уплотнения
Температура выше 38 °C и озноб
Покраснение, расползающееся за пределы уплотнения
Резкая слабость, спутанность сознания, частый пульс
Абсцесс у человека с сахарным диабетом или сниженным иммунитетом

Why does an abscess form?

Any injection causes tissue damage, and normally it heals without a trace. Problems begin when the drug does not enter the muscle, but into the subcutaneous tissue, where it is poorly absorbed and irritates the tissue. This is especially true for oil solutions and drugs with a pronounced irritating effect. An additional contribution is made by impaired skin processing, multiple injections at one point, poor blood supply to the area due to excess weight and diabetes. Microbes from the skin enter damaged tissues and find a favorable environment there.

Penetration of the drug into the subcutaneous tissue
Oily and irritant solutions
Violation of leather treatment rules
Many injections in one place
Excess weight and short needle
Diabetes mellitus and reduced immunity

Infiltration or abscess

Infiltration is a dense, painful compaction without a cavity with pus. The skin over it may be slightly pink, but the pain is moderate and the general condition does not suffer. At this stage, the doctor may prescribe local remedies and physical therapy, and the lump will resolve. An abscess is distinguished by the fact that a cavity has already formed inside: the pain becomes twitching, intensifies at night, the skin turns red and becomes hot, softening appears in the center, and the temperature rises. Ultrasound of soft tissues helps to accurately distinguish between these conditions, so a doctor’s examination is needed in both cases.

Infiltration: dense compaction, moderate pain
Abscess: throbbing pain and softening in the center
Redness and local increase in skin temperature
General temperature and chills with abscess
Ultrasound distinguishes pus from infiltrate

What not to do

The most common and dangerous mistake is to heat the injection site. When purulent inflammation has already begun, heat accelerates the melting of tissue, and a limited abscess can turn into phlegmon with the spread of pus throughout the muscle spaces. Do not squeeze, pierce the seal with a needle, or open it yourself. Iodine nets and compresses with alcohol do not replace examination and can cause burns. Also, you should not start antibiotics on your own: once an abscess has formed, they do not penetrate into the cavity and only blur the picture.

Do not apply a heating pad or warm compresses
Do not squeeze or puncture the seal.
Do not use alcohol compresses
Do not take antibiotics unless prescribed
Do not continue injections in the same place
Contact a surgeon rather than wait for spontaneous resorption

How does a surgeon treat

A formed abscess can only be treated surgically: the doctor, under anesthesia, opens the cavity, removes pus and dead tissue, washes the wound and leaves a drainage so that the discharge can come out freely. This is followed by regular dressings until the wound is cleansed and healed. Antibiotics are prescribed for widespread inflammation, high fever, diabetes mellitus and reduced immunity, and not for everyone. Small abscesses are opened on an outpatient basis, large and deep ones require hospitalization. After healing, a small scar may remain on the skin.

Opening and draining the cavity
Removing pus and dead tissue
Regular dressings
Antibiotics according to indications
Hospitalization for deep and large abscesses
Glucose control in diabetes

How to avoid

Intramuscular injections are made into the upper outer quadrant of the buttock or into the outer surface of the thigh, with a needle of sufficient length so that the drug gets into the muscle. The skin is treated with an antiseptic and allowed to dry, only disposable syringes are used, and the ampoule is opened immediately before administration. Oil solutions are introduced slowly and pre-warmed in the hands to body temperature. The injection sites are alternated, and after the injection, a dry cloth is briefly pressed without rubbing. If a lump appears, inform the doctor immediately.

Inject into the upper outer quadrant of the buttock or thigh
Use a needle of sufficient length
Treat the skin with an antiseptic and let it dry
Alternate injection sites
Introduce oil solutions slowly
Tell your doctor about any lump immediately

Services and prices for this diagnosis

Based on official price lists of Tashkent clinics. The exact cost is determined after examination.

🔬 Diagnostics

Первичный приём хирургаfrom 200 000 УЗИ мягких тканей (поверхностные образования)from 130 000 Общий клинический анализ крови + СОЭfrom 75 000

💊 Treatment

Вскрытие абсцесса мягких тканей Перевязка гнойной раны

Frequently asked questions: Abscess after injection (post-injection)

Is it possible to warm the bump after the injection?+

No. If purulent inflammation begins, heat accelerates the melting of tissues and contributes to the transition of the abscess into phlegmon. If a lump appears with pain and redness, you need to be examined by a surgeon, who will decide what to do after an ultrasound.

How many days after the injection does an abscess appear?+

Induration usually occurs in the first days, and signs of suppuration appear after a few days or within one to two weeks. Key signs that it has become an abscess include tugging pain, redness, hot skin, central softening, and temperature.

Is it always necessary to open an abscess?+

If a cavity with pus has already formed, yes: antibiotics and ointments do not penetrate inside it. At the stage of infiltration without pus, the doctor may prescribe local treatment and observation. Ultrasound of soft tissues helps to distinguish one from the other.

Will there be a scar?+

After opening a small abscess, an inconspicuous scar usually forms. With large and deep ulcers, the scar is more pronounced. The earlier the autopsy is performed, the less the amount of intervention and the better the cosmetic result.

Why does an abscess occur more often after injections in the buttock?+

There is a pronounced layer of subcutaneous tissue, and with a short needle or incorrect technique, the drug does not enter the muscle, but into the adipose tissue, where it is poorly absorbed. The risk is higher if you are overweight and have long courses of injections.

The information on this page is for reference only and does not replace a doctor consultation. Only a qualified specialist can make a diagnosis and prescribe treatment after an in-person examination.