Treatment of Infectious Diseases
› Drugs used to treat bacterial diseases are grouped into categories based on their modes of action
Treatment of Bacterial Diseases
›Penicillins and cephalosporins
› Interfere with certain layers of the bacteria’s cell wall
› Do not affect the host cells
Treatment of Bacterial Diseases
› Chloramphenicol, Tetracyclines, and Erythromycins
› Bind to bacteria cell ribosomes and inhibits protein synthesis
› May be toxic to human tissue when used in high doses or for prolonged periods of time
Treatment of Bacterial Diseases
›Rifampin› Used to treat
tuberculosis› Inhibits RNA synthesis
Treatment of Bacterial Diseases
›Drugs that effectively inhibit viral infections are highly toxic to host cells because viruses use the host’s metabolic enzymes in reproduction
Treatment of Viral Diseases
› Antiviral drugs target virus-specific enzymes
› Acyclovir Used in treatment of
genital herpes
Treatment of Viral Diseases
› Amantadine› Used to prevent or
moderate influenza (flu) for those at high risk of severe illness
› AZT› Inhibits replication of
HIV genome
Treatment of Viral Diseases
› Development of drugs used treat fungi, protozoan, and helminthic diseases are also highly toxic to mammals
Treatment of Fungal and Parasitic Diseases
› Azol Derivitives › Antifungal› Inhibit sterol synthesis› Sterols are organic
compounds that make up cell walls
Treatment of Fungal and Parasitic Diseases
› Amphotericin B› Antifungal also› Disrupts cell membrane
Treatment of Fungal and Parasitic Diseases
Antimicrobial resistance presents ongoing problems in the fight against infectious diseases
RESISTANCE TO ANTIMICROBIAL AGENTS
› Penicillin resistance noted as early as 1943 by Alexander Fleming (the discover of penicillin)
› He warned that indiscriminate use of penicillin would lead to resistant pathogenic bacteria
Resistance to Antimicrobial Agents
Mycobacterium Tuberculosis (TB)
Some strains are resistant to all of the currently available drugs used for treatment
Resistance to Antimicrobial Agents
› Is a result of changes in genetic information› Resistance mechanism include:› 1. Causes structural changes that inhibit the
drug’s ability to bind to it› 2. Reduces permeability of the cell membrane to
the drug› 3. Actively pumps the drug out of the cell after it
has entered it
Resistance to Antimicrobial Agents