Skin infection: what causes it and what you can do now

Redness, swelling, pus, or a sore that won’t heal — those are the signs most people notice first. Skin infections come from bacteria, fungi, viruses, or even tiny parasites. Some are mild and clear with basic care. Others need antibiotics or urgent medical attention. Knowing the difference helps you act fast and avoid complications.

Bacterial infections include impetigo, cellulitis, and abscesses. MRSA (a resistant Staph strain) can cause painful, pus-filled bumps. Fungal infections like ringworm or yeast often itch and have clear edges. Viral infections such as cold sores follow a different pattern and may need antiviral drugs. The treatment depends on which germ is causing the problem.

Treatment basics

Start simple: keep the area clean with soap and water, cover open wounds, and use a warm compress for pain or to help drainage. Small, localized infections sometimes respond to topical antibiotics or antifungal creams. Deeper or spreading infections usually need oral antibiotics. For abscesses, a doctor may need to drain it — don’t try to squeeze it yourself.

Common antibiotics used for skin infections include cephalexin, doxycycline, and trimethoprim-sulfamethoxazole (often used when MRSA is a concern). Tetracycline-class drugs are also used; read our article “Tetracycline: Uses, Side Effects, and Safe Antibiotic Practices” for details on safe use. For fungal issues, topical clotrimazole or oral fluconazole may be recommended. Always follow a prescriber’s dose and finish the full course unless instructed otherwise.

When to see a doctor and red flags

See a clinician if the redness spreads, you have a fever, severe pain, or red streaks moving away from the site. Also seek care if an infection won’t improve within 48–72 hours of basic care, or if you have diabetes, immune problems, or poor circulation — infections can get serious fast in those situations.

Ask for a wound culture if treatment isn’t working or if the doctor suspects resistant bacteria. That test tells you which antibiotic is likely to work. If you’re told to take antibiotics, don’t stop early just because you feel better. Stopping too soon can let the infection return and encourage resistance.

Simple prevention helps a lot: keep cuts clean, wash hands, avoid sharing towels, treat athlete’s foot promptly, and manage chronic conditions like diabetes. If you’re buying medications online, check that the pharmacy is legitimate and requires a prescription when appropriate.

Want more reading? Check our pieces on treatment choices and complications, like “Tetracycline: Uses, Side Effects, and Safe Antibiotic Practices” and “Understanding and Preventing Candidemia.” Those articles give more detail on antibiotic choices, side effects, and when infections move beyond the skin.

If you’re unsure whether your rash or sore is an infection, call a healthcare provider — quick action usually makes recovery faster and safer.