Cellulitis: symptoms, treatment, recovery and when it is an emergency

The NHS says cellulitis makes your skin painful, hot and swollen. The area usually looks red, though this may be less obvious on brown or black skin, and the skin may be blistered. You may also feel unwell with flu-like symptoms and swollen, painful glands.

NHS inform says cellulitis causes an area of skin to suddenly become red, hot, swollen, painful and tender. It most often affects the lower legs but can happen anywhere. The NHS notes it can affect the hands, causing swelling in fingers or the back of the hand, and the feet, sometimes near the toes if you have athlete's foot. Cellulitis in or around the eye is very serious.

The NHS says that for mild cellulitis affecting a small area of skin, a doctor will prescribe antibiotic tablets, usually for a week. Symptoms might get worse in the first 48 hours of treatment but should then start to improve. It is important to keep taking antibiotics until they are finished, even when you feel better. If cellulitis is severe, you might be referred to hospital for treatment.

NICE Clinical Knowledge Summaries lists reasons for hospital referral or admission, including being severely unwell, frail, immunocompromised or very young, facial cellulitis or infection near the eyes or nose, a spreading infection not responding to oral antibiotics, and being unable to take oral antibiotics.

The NHS says most people make a full recovery after 7 to 10 days. A course of antibiotics is usually a week for mild cellulitis. Contact your GP if you do not start to feel better 2 to 3 days after starting antibiotics, and note that symptoms might worsen briefly in the first 48 hours.

NICE Clinical Knowledge Summaries says most episodes resolve with treatment, but recurrence is common and each episode increases the likelihood of another.

No. Both the NHS and NHS inform say you cannot catch cellulitis from another person, because it affects the deeper layers of the skin. The bacteria usually enter through broken skin, so you cannot pick it up from casual contact with someone who has it.

The NHS says cellulitis is usually caused by a bacterial infection. The bacteria can infect the deeper layers of the skin if it is broken, for example because of an insect bite or cut, or if it is cracked and dry. Sometimes the break in the skin is too small to notice. NICE Clinical Knowledge Summaries names Streptococcus pyogenes and Staphylococcus aureus as the most common bacteria.

• poor circulation in the arms, legs, hands or feet, for example because of being overweight

• finding it difficult to move around

• a weakened immune system, for example from chemotherapy or diabetes

• lymphoedema, which causes fluid build-up under the skin

• injecting drugs

• a wound from surgery

• having had cellulitis before

The NHS says to call 999 or go to A&E if you have cellulitis with any of the following, which are symptoms of serious complications that can be life threatening. NHS inform adds symptoms that are getting rapidly worse, a face or area around the eye that is affected, and a weak immune system.

• a very high temperature, or feeling hot, cold or shivery

• a fast heartbeat or fast breathing

• purple patches on the skin (may be less obvious on brown or black skin)

• feeling dizzy or faint

• confusion or disorientation

• cold, clammy or pale skin

• unresponsiveness or loss of consciousness

The NHS says some people with recurring cellulitis might be prescribed low-dose long-term antibiotics to stop infections coming back. It also suggests the following. People at higher risk should treat athlete's foot promptly.

• keep skin clean and well moisturised

• clean any cuts or wounds and use antiseptic cream

• prevent cuts and scrapes by wearing appropriate clothing and footwear

• wear gloves if working outside

• treat athlete's foot promptly if you are at higher risk

NICE Clinical Knowledge Summaries lists deep vein thrombosis, septic arthritis, acute gout and a ruptured Baker's cyst among the conditions that can look like cellulitis, and says the diagnosis can usually be made on history and examination alone. The NHS notes impetigo is a different, more superficial skin infection.

On the NHS, cellulitis is assessed by a GP or NHS 111, usually with oral antibiotics at home and hospital treatment for severe cases. Because it can worsen quickly, same-day assessment matters more than the choice of provider. Private urgent care or GP services can also assess cellulitis; the treatment and warning signs are the same, and A&E or 999 remains the route for the emergency signs above.