Azithromycin for cellulitis: what to know

The choice depends on the likely bacteria, local resistance patterns, medicine allergies, other health conditions and how severe the infection appears. A clinician may prefer a different antibiotic that more reliably covers the suspected bacteria.

Cellulitis is an infection in deeper layers of skin and the tissue beneath. It commonly presents with expanding redness, warmth, swelling and tenderness, sometimes with fever. Treatment needs to reach the bacteria responsible; an antibiotic that does not cover them can allow the infection to progress.

Azithromycin is a macrolide antibiotic. It may be considered when specific clinical circumstances make it appropriate, including some antibiotic allergies, but it should not be borrowed or started from leftover tablets. A cracked area between the toes, wound or other break in the skin may also need attention to reduce repeat infection.

Take azithromycin exactly as written on the prescription and complete the prescribed course unless the prescriber tells you to stop. Tell the clinician about medication allergies, pregnancy, liver problems, heart-rhythm conditions and all medicines or supplements you use. Seek advice if you vomit a dose or miss one rather than doubling it.

Rest and elevate the affected limb when practical. Watch whether redness spreads, pain intensifies or swelling increases. Do not massage the area or apply unprescribed creams to broken skin. Arrange reassessment if symptoms are not beginning to settle as expected or worsen at any point; the diagnosis, antibiotic or route of treatment may need to change.

Get urgent medical assessment for rapidly spreading redness, severe or escalating pain, marked swelling, blistering, dark or numb skin, red streaks, fever with shaking chills, confusion, faintness, breathing difficulty or reduced alertness. Infection near an eye also needs prompt assessment.

After azithromycin, emergency help is needed for facial or throat swelling, wheezing, collapse, or a widespread blistering rash. Contact the prescriber promptly for persistent severe diarrhoea, yellowing of the eyes or skin, or a new racing or irregular heartbeat.

Ask which bacteria the treatment needs to cover, why azithromycin is preferred in your case, when improvement should become noticeable, and what change should trigger reassessment. Also ask whether a wound, athlete's foot, leg swelling or diabetes needs separate management.