How does Zosyn treat pneumonia?

A powerful antibiotic, Zosyn can be used to treat bacterial pneumonia. It also can be used to treat a type of pneumonia called mycoplasmic pneumonia. It cannot be used to treat other forms of pneumonia caused by a virus or fungus. Likewise, it is not always effective in treating bacterial infections, as some bacteria that cause pneumonia may be resistant to Zosyn and other penicillins.