Antibiotics

Antibiotic. Antibiotics are substances which are used to treat different type of infestation of the human organism by viruses bacteria, fungi or protozoa. Antibiotics work by killing or inhibiting the growth of the mentioned biota. That's why anti-viral, anti-fungal, and anti-parasitic drugs can be also called antibiotics. Antibiotics are obtained from microorganisms or through a half-synthetic approach. Natural antibiotics more often are produced by actinomycetes. Antibiotics are divided into 3 groups by the possible effect on the foreign microorganisms:  Bacteriostatic (microorganisms are alive but cannot reproduce)  Bactericidal (microorganisms are killed, but they are still present in the body)  Bacteriolitic (microorganisms are killed, and there cellular wall is dissolved) Antibiotic treatment consists in making the correct choice of necessary drug which is harmless to the host and in the same time effective against microorganisms which cause the infection. The effectiveness of an antibiotic depends on the ability of bacteria to resist or inactivate it.