Skin infections — when treatment is needed
Reviewed by the My London Pharmacy clinical team, Yousef Yaghoubi, Pharmacist
·29 July 2026
·7 min read
Quick answer
Skin infections happen when bacteria, fungi or viruses enter the skin, often through a cut, bite or patch of broken skin. Many minor infections settle with good care, but spreading redness, pus, pain or fever may need treatment such as an antibiotic cream or tablets. A clinician can advise when medical treatment is needed.
What skin infections are
The skin is the body's largest organ and its first line of defence, so it is constantly exposed to the microbes around us. Usually it keeps them out, but when the barrier is broken by a cut, scratch, insect bite, or a condition such as eczema, bacteria, fungi or viruses can get in and cause an infection. Skin infections range from very minor and self-limiting to more serious problems that need prompt treatment.
Knowing the type of infection matters, because bacterial, fungal and viral infections are treated very differently. Recognising the signs, and knowing when a minor problem has become one that needs attention, helps you get the right care at the right time and avoid complications. Most skin infections are minor and settle quickly, but a small number can spread or become serious if they are not treated, so it is useful to know both how to care for the everyday ones and which warning signs mean it is time to seek help.
Bacterial skin infections
Bacterial infections often develop where the skin is already broken. Common examples include impetigo, a contagious infection that causes golden crusted sores, and infected wounds or hair follicles. A more serious bacterial infection is cellulitis, where the skin becomes hot, red, swollen and tender over a spreading area, sometimes with fever.
Minor, localised bacterial infections may be treated with a topical antibiotic such as Fucidin. Where infection is associated with inflamed or eczema-prone skin, a combined preparation like Fucibet or Trimovate, which pair an antibiotic with a steroid, may be considered. More extensive infections such as cellulitis usually need oral antibiotics and prompt assessment, in line with NICE guidance, because they can spread quickly.
It is helpful to know that not every red or sore patch of skin is infected; inflammation from eczema or an allergic reaction can look similar without any infection being present. This is one reason antibiotics are not the answer to every skin complaint, and using them only when genuinely needed helps keep them working well for everyone. If a bacterial infection is confirmed and treated, it is important to complete the course as directed and to watch for improvement over the following days.
Fungal skin infections
Fungal infections thrive in warm, moist areas of skin. Common examples include athlete's foot between the toes, ringworm on the body, and thrush-type infections in skin folds. They typically cause itching, redness, scaling and sometimes a ring-shaped rash, and they are usually more irritating than dangerous.
Most fungal skin infections respond well to antifungal creams, and many can be managed with pharmacy treatments. Because fungal and bacterial infections look different and need different medicines, it helps to identify which you are dealing with. A clinician or pharmacist can guide you if you are unsure, particularly if a rash is not settling with the treatment you have tried.
Viral skin infections
Viruses cause several familiar skin conditions, including warts and verrucas, cold sores, and the shingles rash. These behave differently from bacterial and fungal infections and often follow their own course. Cold sores, for example, tend to recur, while warts may eventually clear on their own over time.
Some viral skin infections benefit from specific antiviral treatment, particularly if caught early or if they are severe, while others are simply managed for comfort. Because the right approach depends on the specific infection, it is worth seeking advice rather than assuming a cream intended for one type of infection will help another. Using the wrong treatment can sometimes make matters worse, for example applying a steroid cream to something that is actually infected, or an antibiotic cream to a viral or fungal problem it cannot touch. Shingles in particular can be helped by antiviral treatment if it is started early, which is one reason a prompt, accurate assessment is so valuable when a new or spreading rash appears.
Why some people are more prone to infections
Anyone can develop a skin infection, but some people are more susceptible than others. A broken skin barrier is the most common way in, so conditions that damage or dry the skin, such as eczema, or injuries like cuts, grazes, bites and burns, all raise the risk. Skin that is frequently wet, or areas that rub together in warm skin folds, can also become vulnerable.
The body's ability to fight off infection matters too. People with diabetes, those taking medicines that suppress the immune system, and anyone whose circulation is reduced may find that infections take hold more easily and are slower to heal. For these groups, what might be a minor problem for someone else can become more significant, so early advice is sensible. Keeping the skin healthy and intact, managing underlying skin conditions well, and treating small breaks in the skin promptly all help reduce the chance of an infection developing in the first place.
Caring for minor skin infections
Many minor skin problems can be managed at home with simple care. Keep the affected area clean, wash your hands before touching it and again afterwards, and cover broken skin with a clean dressing where appropriate. Avoid squeezing or scratching, which can spread infection and delay healing. Good general skin care, including moisturising dry or eczema-prone skin, helps keep the barrier intact and prevents infections taking hold.
If you are treating a minor infection yourself, keep an eye on it. Improvement over a few days is reassuring, whereas an area that is getting larger, more painful or more inflamed is a sign to seek advice rather than continuing to wait.
Warning signs that need attention
Some situations need prompt medical assessment. Seek advice without delay if you notice:
- Redness that is spreading or a red streak moving away from the area
- Increasing pain, swelling or warmth
- Pus, or a wound that will not heal
- A fever or feeling generally unwell alongside a skin infection
- An infection in someone with diabetes or a weakened immune system
These can indicate a deeper or spreading infection such as cellulitis that needs treatment. Facial infections, infections near the eyes, and rapidly worsening symptoms should always be taken seriously and assessed quickly.
Getting the right treatment
Because skin infections vary so much, the right treatment depends on identifying the cause and how far it has spread. A clinical consultation allows the type of infection to be assessed and a suitable treatment recommended, whether that is a topical antibiotic, an oral course, or an antifungal or antiviral where appropriate.
Treating an infection promptly and correctly reduces the risk of it spreading or recurring. All treatment is subject to suitability, and a clinician can advise on the safest option based on your symptoms and medical history.
If you have recurrent skin infections, it is worth looking beyond each individual episode to what might be making them keep happening. Sometimes the answer lies in an underlying skin condition such as eczema that leaves the barrier vulnerable, sometimes in a source of infection that has not been cleared, and occasionally in a general health factor that a clinician can help identify. Addressing the root cause, rather than repeatedly treating flare after flare, often breaks the pattern. Simple measures make a difference too: keeping skin well moisturised and intact, cleaning and covering wounds promptly, maintaining good hand hygiene, and not sharing towels or personal items all reduce the chance of infection taking hold in the first place. If infections keep returning despite these steps, a review can help pinpoint what is going on and put a longer-term plan in place.
Frequently asked questions
How do I know if a skin infection is serious?
Warning signs include spreading redness, increasing pain, swelling, pus, or feeling unwell with a fever. These suggest the infection may be spreading and need prompt medical assessment.
Can I treat a skin infection with cream from the pharmacy?
Minor, localised infections can sometimes be managed with pharmacy or prescribed creams, but the right product depends on whether it is bacterial, fungal or viral. A pharmacist or clinician can help you choose.
Are skin infections contagious?
Some are, such as impetigo, ringworm and cold sores, which can spread through contact or shared items. Washing hands and not sharing towels reduces the risk of passing them on.
Why do I keep getting skin infections?
Recurrent infections can be linked to broken or dry skin, conditions such as eczema, or a weakened immune system. If infections keep returning, it is worth a review to look for an underlying cause.
When do I need antibiotics for a skin infection?
Antibiotics are considered when a bacterial infection is spreading, not settling, or causing symptoms such as fever. A clinician decides based on the type and severity of the infection.