Definition
Antibiotics are used for treatment or prevention of bacterial infection.
They may be informally defined as the subgroup of anti-infectives that are
derived from bacterial sources and are used to treat bacterial infections.
Other classes of drugs, most notably the
sulfonamides
, may be effective antibacterials. Similarly, some antibiotics may have
secondary uses, such as the use of demeclocycline (Declomycin, a
tetracycline derivative) to treat the syndrome of inappropriate
antidiuretic hormone (SIADH) secretion. Other antibiotics may be useful in
treating protozoal infections
