Question

Which one of the following is not a broad spectrum antibiotic?
A.Tetracycline
B.Chloromycetin
C.Penicillin
D.None of these

Answer 1

Hint:A broad-spectrum antibiotic is an antibiotic that acts on the two major anti-bacterial groups, gram-positive and gram-negative and even other antibiotics that act against a wide range of disease causing bacteria.

Complete answer:
Antibiotics are often grouped by their ability to act on different bacterial groups. For example, the first generation cephalosporins are primarily more effective against gram-positive bacteria while the fourth-generation cephalosporins are more effective against the gram-negative bacteria.
Common examples of broad spectrum bacteria include, doxycycline, minocycline, chloromycetin, tetracycline, chloramphenicol, etc.
Penicillin is not a broad-spectrum antibiotic because it has a narrow spectrum and is used to treat only certain infections caused by the streptococci and staphylococci bacteria such as pneumonia. It is group of antibiotics that is derived from the common moulds called the Penicillium moulds and includes penicillin G (administered intravenously), penicillin V (taken orally), procaine penicillin and benzathine penicillin (for intramuscular use).

Hence, the correct answer is option C.

Note:
There are about 10-100 trillion organisms that colonize the human body. As a side-effect of the therapy the antibiotics may change the normal antibody count of the body by attacking both the pathological as well as the naturally occurring antibodies which are harmless, in fact the beneficial bacteria that occur in the gut, lungs, bladder, intestines, etc. The uses of doxycycline for the treatment of acne vulgaris can aggravate the problem of Crohn’s disease.