What is an antibiotic?

An antibiotic is any substance that interferes with the ability of bacteria to function normally (remember, bacteria are living organisms). It may either inhibit their growth (bacteristatic antibiotic) or kill the bacteria (bactericidal antibiotic).

Antibiotics are used to treat bacterial infections ranging from life-threatening meningitis to common problems like acne and strep throat. Antibiotics will not help cure illnesses caused by viruses, such as colds or flu.