Without prompt medical care, cellulitis can spread through the body and cause sepsis, a serious blood infection. Seek emergency medical care if you notice signs of sepsis, including: Confusion Fast heart rate Fever Trouble breathing Worsening rash or pain Prompt medical care can prevent serious complications from cellulitis. Oral antibiotics (pills) usually clear up the infection quickly and stop it from spreading. Cellulitis isn’t contagious, so it does not spread from person to person.