chapter 20 Flashcards
narrow spectrum antibiotics
only kill or inhibit limited species of bacteria
broad spectrum antibiotics
kill or inhibit gram negative and gram positive
superinfection
overgrowth of normal microbiota that is resistant to antibiotics
bactericidal
kill microbes leaving nothing behind
bacteriostatic
prevent microbes from growth
action of antimicrobials
- inhibit cell wall synthesis
- injuring plasma membrane
- inhibit protein synthesis
- inhibit nucleic acid syn
- inhibit syn of essential metabolites
antiviral drugs types
- entry and fusion inhibitor
- block receptor on host that bind to virus
- block fusion of virus and cell - uncoating, genome integration and nucleic acid
synthesis inhibitors
- prevent viral uncoating
- inhibit viral DNA integration into host genome
- nucleoside analog inhibit rna/dna synthesis
assembly and exit inhibitors
protease inhibitors - block cleavage of protein
precursors(in hiv)
interferons - made by viral infected cells to stop
spread of infection(imiquimod : promote interferon prod)
antiretrovirals for HIV/AIDS(rna virus) - AZT interfere w reverse transcriptase
persister cells
microbe w genetic characteristic that allow for survival when exposed to antibiotic
superbugs
bacteria resistant to large number antibiotics
mechanism of resistance to antibiotics
- enzymatic destruction or inactivation of drug
- prevent penetration of target site on microbe
- alter drug target site
- fast ejection of antibiotic
misuse of antibiotics
- use outdated or weakened antibiotics
- using antibiotic for common cold or inappropriate conditions
- use antibiotic in animal feed
- no use all prescribed regimen
- using someone leftover prescription
synergism
effect of 2 drugs together greater than alone
antagonism
effect of 2 together is less than either alone
how does penicillin work
- prevent synthesis of peptidoglycan
