Erythromycin

Erythromycin is a Macrolide antibiotic which has a spectrum of activity which is similar to that of Penicillin so it is used in those who have an allergy to penicillins. For respiratory tract infections[?], it has better cover of atypical organisms, including Mycoplasma.

Otherwise a great antibiotic for treating community respiratory tract infections, a significant number of people unfortunately have serious gastrointestinal upsets as a side-effect of this antibiotic so it tends not to be prescribed as a first line drug.