What the different between broad spectrum and macrolid antibiotic? which one more strong side effects ?

Tough comparison: Broad spectrum is a relative term. For example, the macrolides have a broader spectrum than penicillin, and the quinolones have a broader spectrum than the macrolides. A broader spectrum will kill more types of bacteria and is useful when the organism one needs to kill is not known precisely. Broader spectrum drugs will also kill more natural gut bacteria and are more likely to cause diarrhea.