Chapter 10- controlling Microbial Growth in the Body: Antimicrobial drugs

Chemotherapeutic agents

Drugs that act against diseases

Antimicrobial agents

Drugs that treat infections

Antibiotics

Antimicrobial agents produced naturally by organisms

Semi-synthetic antibiotics

Chemically altered antibiotics that are more effective than naturally occurring ones

Synthetic antibiotics

antibiotics that are completely synthesized in a lab

Selective toxicity

A drug that kills harmful microbes without damaging the host

Broad spectrum antibiotics

Effective against many species

Narrow spectrum antibiotics

Effective against a narrow range of bacteria

Vancomycin

Used to treat MRSA

Bacitracin

Topical application, toxic to kidneys

Isoniazid

Used for mycobacteria

Polymyxin B

Changes membrane permeability leading to lysis, combines with bacitracin and neomycin to make neosporin

Rifampin

Used for TB

Fiprofloxacin

Used against bronchitis and urinary tract infections caused by gram + bacteria

Amphotericin B

Antifungal: attaches to ergosterol in fungal membranes

Acyclovir

Antiviral: used against Herpes virus- nucleotide analog

AZT

Reverse transcriptase inhibitor: used in HIV treatment

Enzymatic destruction

Produce an enzyme that destroys or deactivates the drug

Prevention of penetration

May slow or prevent the entry of the drug into the cell

Alternation of the drug’s target site

Drug cannot attach or binds less effectively

Rapid ejection

pump the antimicrobial out of the cell

Superbugs

Resistance to many or all antibiotics

Synergism

Work more effectively together, broader spectrum, less chance of resistance

Antagonism

Two opposing antimicrobials cancel out each others’ effects