Medicines for Cellulitis

What it is

Cellulitis is an infection of the deeper layers of the skin and the soft tissue underneath, caused by bacteria getting in through a break in the skin such as a cut, graze, insect bite, athlete's foot between the toes, a leg ulcer or an area of eczema. The affected area becomes hot, red, swollen and tender, often with the skin looking tight or shiny, and it usually appears on one side of the body — most commonly a lower leg — rather than affecting both legs equally. Some people also feel generally unwell, shivery or feverish as the infection takes hold. Because the redness can spread, it helps to notice how far it reaches when it starts. Cellulitis is treated promptly because, left unchecked, the infection can spread more widely or deeper. It is also worth distinguishing from look-alikes such as a deep-vein clot (DVT) or long-standing venous eczema, which can also cause a red, swollen lower leg but are not the same thing and need different care.

How it is treated

The aim is to clear the infection, settle the inflammation and watch for any sign that it is spreading or becoming more serious. Treatment usually centres on a course of antibiotics taken by mouth, chosen to cover the bacteria that most often cause cellulitis; flucloxacillin, a penicillin-type antibiotic, is the usual first choice, while a macrolide such as clarithromycin is used for people who are allergic to penicillin. It is important to finish the full course even once the skin starts to look better. Alongside antibiotics, the leg or affected part is often raised when resting to reduce swelling, and any underlying entry point — such as athlete's foot, a wound or dry cracked skin — is treated so the infection is less likely to return. A simple but useful step is to draw around the edge of the redness with a pen so that you and any clinician can tell whether it is shrinking with treatment or still spreading, which guides whether the current plan is working.