Skin Glossary · Distinguishing between conditions and causes

Secondary Infection

Name: Meaning of Secondary Infection
Published: 2026-08-25

Related terms · aggravated skin · bacterial infection

Secondary infection refers to cases where an infection is added on top of eczema or scratched wounds. Pain, heat sensation, pus, yellow scabs, and rapid spread can be clues.

Reviewed by Korean Medicine Doctor Choi Yeon-seung · Last updated 2026-08-25

Key Points

Secondary Infection: Please check these three things first

A secondary infection occurs when a bacterial, viral, or fungal infection is added to pre-existing eczema or scratches.
Clear discharge alone does not confirm an infection, but prompt medical evaluation is necessary if it is accompanied by pain, heat, pus, yellow crusts, rapid spreading, and fever.
If an infection is suspected, do not wait for a Korean medicine clinic appointment or moisturizing care; instead, seek the necessary anti-infective treatment first.

What is a secondary infection?

It is a condition where a bacterial, viral, or fungal infection is added to pre-existing dermatitis or scratches. A secondary infection refers to cases where an infection is added on top of eczema or scratched wounds. Pain, heat, pus, yellow crusts, and rapid spreading can be clues.

How is it different from similar conditions?

An infection is not confirmed by clear discharge from eczema alone. Systemic symptoms and changes in the lesion are evaluated together.

Why is this important in skin care?

It must be determined whether infection treatment should be received first.

What should be checked based on my symptoms?

If there is fever, rapid spreading, or involvement around the eyes, immediate and appropriate medical evaluation takes priority over scheduled Korean medicine treatments.

Context

Check for pain, heat, and spreading that differ from usual flare-ups

Existing eczema can be itchy and produce discharge, but if it suddenly becomes painful and hot, or if pus and yellow crusts increase and the red area expands rapidly, an aggravated infection must be checked. Take photos under the same lighting and record the starting point, the area it spread over one day, and your body temperature.

Context

Evaluate more quickly if there is swelling around the eyes, systemic symptoms, or compromised immunity

Do not wait for a scheduled appointment if the area around the eyes is swollen and painful, or if fever, chills, or lethargy occur. If you have diabetes or are receiving immunosuppressive therapy, notify medical staff immediately. Using non-prescribed antibiotic ointments or a family member's medication arbitrarily may delay the identification of the cause.

Frequently Asked Questions

Frequently Asked Questions regarding secondary infections

Is all discharge a sign of bacterial infection?

No. Clear discharge can also occur in acute eczema. Whether it is an infection is evaluated by checking for pain, heat, pus, yellow crusts, rapid spreading, and fever together.

Can I apply an antibiotic ointment I have at home first?

Treatment varies depending on the cause and location, so please avoid arbitrary use. Inform the provider about any topical agents used and your allergy history, and have the lesion examined to determine the necessary treatment.

Related conditions and medical guidance

Check guides where this term is used

Condition GuidanceAtopic DermatitisAtopic dermatitis is not confirmed by a single blood test or allergy test. In dermatology, the process centers on observing the appearance and distribution of dryness, itching, and rashes, as well as inquiring about the onset, the course of improvement and worsening, sleep disturbance, response to previous treatments, and exposure to irritants such as soap, detergents, scented products, and smoke. Medical history of atopic dermatitis, asthma, or hay fever for yourself and your family is also reviewed. In many cases, a physical skin examination and medical history are sufficient; blood tests or skin biopsies are selected when other causes of rashes must be ruled out. Symptoms, distribution, and progression are interpreted together rather than relying on a single test result.Condition GuidanceEczemaCommon symptoms of eczema include dry, severely itchy skin and rashes. These can occur on the face, inside the elbows, behind the knees, and on the hands and feet; depending on skin tone, they may appear red, brown, purple, or gray, or present as prominent rough bumps. Scratching leads to more swelling and itching, and may cause scratch marks, scaling, cracking, blisters, oozing, or scabs. Prolonged scratching causes the skin to thicken and crack. If you experience unusual pain, heat, yellow scabs, or if clustered blisters are accompanied by fever and fatigue, promptly evaluate for the possibility of infection or herpetic eczema.Condition GuidanceFolliculitisFolliculitis typically appears as small red pimples or pus-filled pustules that suddenly form in clusters around the hair follicles. The area around the skin change may be red, itchy, or burning, and may be painful when pressed; scabs may form after pustules burst. Shallow folliculitis remains as small papules or pustules, but if it deepens, it may look like a large, hard, painful boil or a carbuncle where several boils are connected, increasing the risk of scarring and hair loss. If redness and pain spread suddenly or are accompanied by fever, chills, or body aches, the spreading infection must be promptly evaluated.Medical Evaluation GuideWhen oozing, pus, pain, and fever occur togetherIf there is rapidly spreading redness, pain that makes it difficult to touch, pus or yellow crusts, fever, or severe swelling around the eyes and mouth, we will first connect you to infection treatment or emergency evaluation. If you have difficulty breathing or if your lips or tongue swell, seek emergency help immediately. Once urgent issues are resolved, remaining itchiness and recurring symptoms will be managed through Korean medicine treatment.

Evidence and Update Information

The definitions and safety standards in the materials below were referenced.

American Academy of Dermatology: Atopic Dermatitis Diagnosis and TreatmentWe have reviewed the roles of skin care, topical treatment, and infection evaluation.