Commonly Encountered Commonly Encountered Microbes and the Microbes and the

Antibacterial Drugs used to Antibacterial Drugs used to treat themtreat them

Felix Hernandez, M.D.Felix Hernandez, M.D.

Gram Positive CocciGram Positive Cocci Appearance:Appearance:

Blue and round by microscopyBlue and round by microscopy Have a thick peptidoglycan cell wall that Have a thick peptidoglycan cell wall that

surrounds the bacteriasurrounds the bacteria This wall is impermeable and is responsible for retention This wall is impermeable and is responsible for retention

of the blue dye in gram stainingof the blue dye in gram staining Penicillins, cephalosporins, bacitracin, vancomycin inhibit Penicillins, cephalosporins, bacitracin, vancomycin inhibit

the synthesis of the peptidoglycan cell wallthe synthesis of the peptidoglycan cell wall Common sites of invasion:Common sites of invasion:

Staph aureus and staph epidermidis inhabit most Staph aureus and staph epidermidis inhabit most people’s skin and can infect wounds, surgical sites people’s skin and can infect wounds, surgical sites and indwelling catheters. and indwelling catheters.

They may cause infective endocarditisThey may cause infective endocarditis Streptococous pneumoniae is the cause of Streptococous pneumoniae is the cause of

community acquired pneumonia and adult community acquired pneumonia and adult bacterial meningitisbacterial meningitis

Group A Beta-hemolytic Streptococcus causes Group A Beta-hemolytic Streptococcus causes strep throatstrep throat

If untreated it can cause an immunologic reaction in the If untreated it can cause an immunologic reaction in the heart and joints known as rheumatic fever.heart and joints known as rheumatic fever.

Gram Negative PathogensGram Negative Pathogens Can be divided into four groups:Can be divided into four groups:

1. enterics 1. enterics normally inhabit the GI tract normally inhabit the GI tract Ex: E. coli, Shigella, Salmonella, EnterobacterEx: E. coli, Shigella, Salmonella, Enterobacter

2. Haemophilus influenzae2. Haemophilus influenzae 3. Neisseria3. Neisseria 4. Pseudomonas4. Pseudomonas

Have a thin layer of peptidoglycan that is Have a thin layer of peptidoglycan that is surrounded by an outer membrane which is surrounded by an outer membrane which is made of lipopolysacharrides (LPS) which acts made of lipopolysacharrides (LPS) which acts as a toxinas a toxin

Some strains produce B-lactamase which is a Some strains produce B-lactamase which is a penicillin destroying enzyme that is penicillin destroying enzyme that is concentrated in the space between the outer concentrated in the space between the outer membrane and cell wallmembrane and cell wall

Gram Negative PathogensGram Negative Pathogens Common sites of invasion:Common sites of invasion:

Enterics are responsible for UTI and Enterics are responsible for UTI and aspiration pneumoniaaspiration pneumonia

Neisseria gonorrhea is responsible for the Neisseria gonorrhea is responsible for the STD gonorrheaSTD gonorrhea

Neisseria meningitidis and H. influenzae Neisseria meningitidis and H. influenzae both cause meningitis although H. both cause meningitis although H. influenzae more commonly causes influenzae more commonly causes pneumonia in the elderlypneumonia in the elderly

Pseudomonas aeruginosa is responsible for Pseudomonas aeruginosa is responsible for hospital acquired infections because if hospital acquired infections because if adequate moisture is available it can adequate moisture is available it can colonize any surface in the hospital and is colonize any surface in the hospital and is resistant to many disinfectantsresistant to many disinfectants

AnaerobesAnaerobes Common organisms include Bacteriodes fragilis, Common organisms include Bacteriodes fragilis,

Clostridium difficile, Clostridium botulinum, and Clostridium difficile, Clostridium botulinum, and Clostridium tetaniClostridium tetani C. botulinum causes botulism and C. tetani causes tetanusC. botulinum causes botulism and C. tetani causes tetanus

Metronidazole, chloramphenicol and clindamycin are Metronidazole, chloramphenicol and clindamycin are effective against anaerobic bacteriaeffective against anaerobic bacteria

Infections are frequently encased in an abscess wall Infections are frequently encased in an abscess wall and they produce foul smelling gasand they produce foul smelling gas

They colonize the mouth, GI tract, and skinThey colonize the mouth, GI tract, and skin Infections develop when they penetrate poorly Infections develop when they penetrate poorly

oxygenated tissues such as the diabetic foot or oxygenated tissues such as the diabetic foot or normally sterile tissues like the peritoneum.normally sterile tissues like the peritoneum.

With the use of broad spectrum antibiotics, C. With the use of broad spectrum antibiotics, C. difficile proliferates and releases a toxin that causes difficile proliferates and releases a toxin that causes pseudomembranous colitis.pseudomembranous colitis.

Cell Wall SynthesisCell Wall Synthesis Peptidoglycan chains are synthesized Peptidoglycan chains are synthesized

in the cytoplasm and get transferred in the cytoplasm and get transferred across the plasma membrane and across the plasma membrane and linked to other peptidoglycan chainslinked to other peptidoglycan chains

This results in a chain link that This results in a chain link that surrounds the bacteriasurrounds the bacteria

Human cells don’t have cell walls so Human cells don’t have cell walls so cell wall synthesis inhibitors don’t have cell wall synthesis inhibitors don’t have many side effectsmany side effects

Cell Wall Synthesis InhibitorsCell Wall Synthesis InhibitorsPenicillinsPenicillins

Penicillin G (IV/IM) and Penicillin V (PO)Penicillin G (IV/IM) and Penicillin V (PO) Narrow Spectrum, Penicillinase SensitiveNarrow Spectrum, Penicillinase Sensitive MOA: inhibit cross linking of cell wall componentsMOA: inhibit cross linking of cell wall components DOC for: Staph and Strep, N. meningitidis, C. DOC for: Staph and Strep, N. meningitidis, C.

tetani, Syphilistetani, Syphilis Side Effects: hypersensitivity reactions, Side Effects: hypersensitivity reactions,

neutropenia, nephrotoxicityneutropenia, nephrotoxicity NaficillinNaficillin

Narrow Spectrum, Penicillinase ResistantNarrow Spectrum, Penicillinase Resistant MOA: has a bulky side group that protects it from MOA: has a bulky side group that protects it from

penicillinasepenicillinase DOC for: penicillinase producing StaphDOC for: penicillinase producing Staph Side Effects: severe thrombophlebitis and liver Side Effects: severe thrombophlebitis and liver

toxicity with elevated LFTstoxicity with elevated LFTs

Cell Wall Synthesis InhibitorsCell Wall Synthesis InhibitorsPenicillinsPenicillins

Broad SpectrumBroad Spectrum AmpicillinAmpicillin

MOA: are hydrophilic and can penetrate the porins in Gram MOA: are hydrophilic and can penetrate the porins in Gram ––

Are not effective against pencillinase producersAre not effective against pencillinase producers DOC for: listeria and enterococcusDOC for: listeria and enterococcus Side Effects: DiarrheaSide Effects: Diarrhea

AmoxicillinAmoxicillin MOA: sameMOA: same DOC for: empiric therapy in otitis media, sinusitis and DOC for: empiric therapy in otitis media, sinusitis and

pneumoniapneumonia Side Effects: DiarrheaSide Effects: Diarrhea

Amoxicillin and Clavulanate (Augmentin)Amoxicillin and Clavulanate (Augmentin) MOA: same but the clavulanate inhibits penicillinasesMOA: same but the clavulanate inhibits penicillinases DOC for: Moraxella catarrhalis (OM), H. influenzaDOC for: Moraxella catarrhalis (OM), H. influenza Side Effects: DiarrheaSide Effects: Diarrhea

Cell Wall Synthesis InhibitorsCell Wall Synthesis InhibitorsPenicillinsPenicillins

Anti-PseudomonalsAnti-Pseudomonals TicarcillinTicarcillin

MOA: has a side chain that makes it more MOA: has a side chain that makes it more resistant to penicillinases from gram – speciesresistant to penicillinases from gram – species

DOC for: PseudomonasDOC for: Pseudomonas Side Effects: NoneSide Effects: None

PiperacillinPiperacillin MOA: sameMOA: same DOC for: enterobacteria and gram + cocciDOC for: enterobacteria and gram + cocci Side Effects: Neutropenia and hematologic Side Effects: Neutropenia and hematologic

abnormalitiesabnormalities

Cell Wall Synthesis InhibitorsCell Wall Synthesis InhibitorsCephalosporinsCephalosporins

First Generation- Narrow Spectrum, First Generation- Narrow Spectrum, sensitive to B-Lactamasesensitive to B-Lactamase Cephalexin (Keflex), Cefazolin (Kefzol)Cephalexin (Keflex), Cefazolin (Kefzol)

MOA: Binds penicillin binding proteins and MOA: Binds penicillin binding proteins and inhibits cell wall synthesisinhibits cell wall synthesis

Resistance: bacteria reduce drug permeability, Resistance: bacteria reduce drug permeability, mutate penicillin binding proteins and produce B-mutate penicillin binding proteins and produce B-lactamaselactamase

Spectrum: Gram + cocci except for MRSA and Spectrum: Gram + cocci except for MRSA and some Gram –, Cefazolin is used in surgical some Gram –, Cefazolin is used in surgical prophylaxis and for treating skin and soft tissue prophylaxis and for treating skin and soft tissue infections by Staph or Strep.infections by Staph or Strep.

Side Effects: hypersensitivity reaction, GI Side Effects: hypersensitivity reaction, GI disturbances, possible seizures and confusion disturbances, possible seizures and confusion with Cefazolin, Nephrotoxicitywith Cefazolin, Nephrotoxicity

CephalosporinsCephalosporins Second Generation- Broader Gram – ActivitySecond Generation- Broader Gram – Activity

Cefaclor (Ceclor), Cefuroxime (Cefitin), Cefoxitin, Cefaclor (Ceclor), Cefuroxime (Cefitin), Cefoxitin, CefotetanCefotetan

MOA: same as first gen but resistance to LactamaseMOA: same as first gen but resistance to Lactamase Spectrum: Gram+ cocci with extended Gram – activity Spectrum: Gram+ cocci with extended Gram – activity

with H. influenza, Enterobacter, Proteus and Neisseriawith H. influenza, Enterobacter, Proteus and Neisseria None are effective against pseudomonasNone are effective against pseudomonas

Clinical Uses: otitis media, pharyngitis, sinus, skin and Clinical Uses: otitis media, pharyngitis, sinus, skin and respiratory infectionsrespiratory infections

Cefuroxime is used as a single dose therapy for N. gonorrheaCefuroxime is used as a single dose therapy for N. gonorrhea Side Effects: Same as first genSide Effects: Same as first gen

Cefaclor is associated with serum sickness (delayed allergic Cefaclor is associated with serum sickness (delayed allergic response)response)

CephalosporinsCephalosporins Third Generation- Broad Spectrum, Third Generation- Broad Spectrum,

Resistant to cephalosporinasesResistant to cephalosporinases Ceftriaxone (Rocephin), Ceftazidime, Ceftriaxone (Rocephin), Ceftazidime,

CefepimeCefepime MOA: same as first gen but more resistant to MOA: same as first gen but more resistant to

lactamaseslactamases Spectrum: gram- bacilli, some pseudomonas, Spectrum: gram- bacilli, some pseudomonas,

gram+ cocci (staph and strep)gram+ cocci (staph and strep) Clinical Uses: penetrate the CSF so can be used Clinical Uses: penetrate the CSF so can be used

for CNS infectionsfor CNS infections Side Effects: same as first gen and acalculous Side Effects: same as first gen and acalculous

cholestasischolestasis

Cell Wall Synthesis Cell Wall Synthesis InhibitorsInhibitors

VancomycinVancomycin MOA: prevents transfer of cell wall precursors from MOA: prevents transfer of cell wall precursors from

plasma membrane to cell wallplasma membrane to cell wall Clinical Use: DOC for penicillin or methicilliin Clinical Use: DOC for penicillin or methicilliin

resistant staph and strepresistant staph and strep Side Effects: thrombophlebitis, ototoxicity, Side Effects: thrombophlebitis, ototoxicity,

nephrotoxicity, Red Man Syndrome (IV) nephrotoxicity, Red Man Syndrome (IV) tachy, tachy, flushing, parethesias, hypotension and severe flushing, parethesias, hypotension and severe nephrotoxicitynephrotoxicity

BacitracinBacitracin MOA: inhibits recycling of the carrier which MOA: inhibits recycling of the carrier which

transports cell wall precursors across the plasma transports cell wall precursors across the plasma membranemembrane

Clinical Use: Gram + infections in the skin and eyeClinical Use: Gram + infections in the skin and eye Side Effects: severe nephrotoxicity when Side Effects: severe nephrotoxicity when

administered IMadministered IM Seen in combo with neomycin in NeosporinSeen in combo with neomycin in Neosporin

Cell Wall Synthesis Cell Wall Synthesis InhibitorsInhibitors

CarbapenemCarbapenem Imipinem/Cilastatin, MeropenemImipinem/Cilastatin, Meropenem

MOA: inhibits cross linking of cell wall MOA: inhibits cross linking of cell wall componentscomponents

Cilastatin inhibits renal metabolism of imipinemCilastatin inhibits renal metabolism of imipinem Clinical Uses: DOC for Acinetobacter, used to Clinical Uses: DOC for Acinetobacter, used to

treat Gram + and – including lactamase treat Gram + and – including lactamase producers and pseudomonasproducers and pseudomonas

Side Effects: hypersensitivity. Doesn’t cause Side Effects: hypersensitivity. Doesn’t cause sterile bowel because of low concentration in sterile bowel because of low concentration in the bowelthe bowel

Cell Wall Synthesis Cell Wall Synthesis InhibitorsInhibitors

MonobactamMonobactam AztreonamAztreonam

MOA: Inhibits cross linking of cell wall componentsMOA: Inhibits cross linking of cell wall components Clinical Use: Excellent coverage of Gram – Clinical Use: Excellent coverage of Gram –

including P. aeruginosa. Not active against Gram including P. aeruginosa. Not active against Gram ++

Side Effects: hypersensitivity, seizures, and Side Effects: hypersensitivity, seizures, and hepatitishepatitis

LipopeptidesLipopeptides DaptomycinDaptomycin

MOA: Depolarizes bacterial cell membraneMOA: Depolarizes bacterial cell membrane Clinical Uses: skin infections caused by S. aureus, Clinical Uses: skin infections caused by S. aureus,

MRSA and StrepMRSA and Strep Side Effects: Hepatotoxicity, diarrhea, and rashSide Effects: Hepatotoxicity, diarrhea, and rash

DNA InhibitorsDNA Inhibitors QuinolonesQuinolones

Nalidixic Acid (NegGram)Nalidixic Acid (NegGram) MOA: blocks a subunit of DNA gyrase therefore MOA: blocks a subunit of DNA gyrase therefore

preventing supercoiling and inhibiting DNA preventing supercoiling and inhibiting DNA synthesissynthesis

Clinical Uses: enteric Gram – but not Clinical Uses: enteric Gram – but not PseudomonasPseudomonas

Side Effects: hypersensitivity rxn, Side Effects: hypersensitivity rxn, photosensitivity, seizure, HA.photosensitivity, seizure, HA.

Displaces oral anticoagulants from plasma proteinsDisplaces oral anticoagulants from plasma proteins Causes growth plate arrest so not used in childrenCauses growth plate arrest so not used in children

DNA InhibitorsDNA Inhibitors FluroquinolonesFluroquinolones

NorfloxacinNorfloxacin MOA: inhibits DNA gyrase and topoisomerase activityMOA: inhibits DNA gyrase and topoisomerase activity Clinical Uses: good gram – coverageClinical Uses: good gram – coverage Side Effects: cartilage damaged so children is a CISide Effects: cartilage damaged so children is a CI

Ciprofloxacin (Cipro)Ciprofloxacin (Cipro) MOA: same as aboveMOA: same as above Clinical Uses: excellent Gram – coverage with some Clinical Uses: excellent Gram – coverage with some

Gram +Gram + Side Effects: Same as aboveSide Effects: Same as above

Levofloxacin (Levaquin)Levofloxacin (Levaquin) MOA: Same as aboveMOA: Same as above Clinical Uses: excellent gram – coverage and improved Clinical Uses: excellent gram – coverage and improved

Staph. Coverage, treat legionella and chlamydia atypical Staph. Coverage, treat legionella and chlamydia atypical pneumoniapneumonia

Side Effects: same as aboveSide Effects: same as above

DNA InhibitorsDNA Inhibitors Metronidazole (Flagyl)Metronidazole (Flagyl)

MOA: enters the bacteria and is activated by MOA: enters the bacteria and is activated by reduction of the nitro group. Binds DNA and inhibits reduction of the nitro group. Binds DNA and inhibits its synthesisits synthesis

Clinical Uses: Bacteriodes, Clostridium and Protozoans Clinical Uses: Bacteriodes, Clostridium and Protozoans such as E. histolytica, Trichomonas, and Giardiasuch as E. histolytica, Trichomonas, and Giardia

Side Effects: Disulfiram-like reaction with alcohol Side Effects: Disulfiram-like reaction with alcohol (flushing, vomiting and headache), CNS disturbance, (flushing, vomiting and headache), CNS disturbance, bloating and crampingbloating and cramping

Nitrofurantoin (Macrodantin)Nitrofurantoin (Macrodantin) MOA: mechanism unclear but may damage DNAMOA: mechanism unclear but may damage DNA Clinical Uses: kills many urinary pathogens but not Clinical Uses: kills many urinary pathogens but not

pseudomonaspseudomonas Side Effects: hepatotoxicity, pulmonary fibrosis, Side Effects: hepatotoxicity, pulmonary fibrosis,

neuropathyneuropathy

AntimetabolitesAntimetabolites SulfonamidesSulfonamides

SulfadiazineSulfadiazine MOA: structurally similar to para-amino benzoic acid (PABA) MOA: structurally similar to para-amino benzoic acid (PABA)

and compete with it and prevent it from being incorporated and compete with it and prevent it from being incorporated into folate so you block DNA, RNA or protein synthesisinto folate so you block DNA, RNA or protein synthesis

Clinical Uses: both gram + and -, used to treat uncomplicated Clinical Uses: both gram + and -, used to treat uncomplicated UTI, chancroid, and prophylaxis against rheumatic feverUTI, chancroid, and prophylaxis against rheumatic fever

Side Effects: bone marrow depression, renal toxicity, Side Effects: bone marrow depression, renal toxicity, photosensitivity, hemolysis, Steven-Johnson syndrome (serum photosensitivity, hemolysis, Steven-Johnson syndrome (serum sickness), Kernicterus (compete with bilirubin for albumin sickness), Kernicterus (compete with bilirubin for albumin sites resulting in bilirubin deposited in brain nuclei)sites resulting in bilirubin deposited in brain nuclei)

Trimethoprim/Sulfamethoxazole (TMP/SMZ, Trimethoprim/Sulfamethoxazole (TMP/SMZ, Cotrimoxazole, Septra, Bactrim)Cotrimoxazole, Septra, Bactrim)

MOA: same as above plus prevents reduction of dihydrofolate MOA: same as above plus prevents reduction of dihydrofolate to tetrahydrofolate by inhibiting dihydrofolate reductaseto tetrahydrofolate by inhibiting dihydrofolate reductase

Clinical Uses: enteric gram -, Salmonella, effective for UTI, Clinical Uses: enteric gram -, Salmonella, effective for UTI, acute otitis media and traveler’s diarrhea, used for PCP acute otitis media and traveler’s diarrhea, used for PCP prophylaxis in immunocompromisedprophylaxis in immunocompromised

Side Effects: same as aboveSide Effects: same as above

Protein Synthesis InhibitorsProtein Synthesis Inhibitors Aminoglycosides (bacteriocidal)Aminoglycosides (bacteriocidal)

Gentamycin, Streptomycin, TobramycinGentamycin, Streptomycin, Tobramycin MOA: bind at the 30s/50s subunit interface and results in MOA: bind at the 30s/50s subunit interface and results in

abnormal reading of mRNA and defective protein abnormal reading of mRNA and defective protein synthesissynthesis

Resistance: mutation of binding sites, inhibition of Resistance: mutation of binding sites, inhibition of transport and permeability of the drugstransport and permeability of the drugs

Clinical Uses: aerobic and faculative gram – bacilli, Clinical Uses: aerobic and faculative gram – bacilli, anaerobic bacteria are resistant because transport into anaerobic bacteria are resistant because transport into the organism is oxygen dependentthe organism is oxygen dependent

DOC for E.coli, Proteus and PseudomonasDOC for E.coli, Proteus and Pseudomonas Side Effects: nephrotoxicity (high troughs) and ototoxicity Side Effects: nephrotoxicity (high troughs) and ototoxicity

(high peaks)(high peaks) AmikacinAmikacin

MOA is the same as above but it has a different MOA is the same as above but it has a different resistance profile so it is reserved for use in Gram – resistance profile so it is reserved for use in Gram – infections that are resistant to other aminoglycosidesinfections that are resistant to other aminoglycosides

Protein Synthesis InhibitorsProtein Synthesis Inhibitors ChloramphenicolChloramphenicol

MOA: reversibly binds to the 50s subunit and MOA: reversibly binds to the 50s subunit and prevents the tRNA from associating with peptidyl prevents the tRNA from associating with peptidyl transferasetransferase

Resistance: Acetyl transferases inactivate the drugsResistance: Acetyl transferases inactivate the drugs Clinical Uses: excellent coverage of most gram+ Clinical Uses: excellent coverage of most gram+

and gram – including anaerobes.and gram – including anaerobes. DOC for typhoid fever, H. flu meningitis or epiglottitisDOC for typhoid fever, H. flu meningitis or epiglottitis

Side Effects: reversible bone marrow suppression, Side Effects: reversible bone marrow suppression, aplastic anemia, gray baby syndrome (in newborns aplastic anemia, gray baby syndrome (in newborns abdominal distention, vomiting, cyanosis, abdominal distention, vomiting, cyanosis, hypothermia, collapse and death (40%)hypothermia, collapse and death (40%)

Linezolid (Zyvox)Linezolid (Zyvox) MOA: binds to 50s subunitMOA: binds to 50s subunit Clinical Uses: vancomycin resistant gram +Clinical Uses: vancomycin resistant gram + Side Effects: NoneSide Effects: None

Protein Synthesis InhibitorsProtein Synthesis Inhibitors MacrolidesMacrolides

ErythromycinErythromycin MOA: prevents translocation of polypeptide chain MOA: prevents translocation of polypeptide chain

by binding the P site of the 50s subunitby binding the P site of the 50s subunit Resistance: mutation of binding site by Resistance: mutation of binding site by

methylationmethylation Clinical Uses: bacteria lacking cell walls Clinical Uses: bacteria lacking cell walls

(mycoplasma, legionella and chlamydia), gram + (mycoplasma, legionella and chlamydia), gram + aerobes, gram – aerobes except campylobacter aerobes, gram – aerobes except campylobacter and H. flu. Poor anaerobic coverageand H. flu. Poor anaerobic coverage

DOC for Mycoplasma pneumonia, neonate with DOC for Mycoplasma pneumonia, neonate with chlamydia pneumonia, pertusischlamydia pneumonia, pertusis

Side Effects: GI upset, injections are painful due Side Effects: GI upset, injections are painful due to venodestructionto venodestruction

Protein Synthesis InhibitorsProtein Synthesis Inhibitors Clarithromycin (Biaxin)Clarithromycin (Biaxin)

MOA: sameMOA: same Resistance: sameResistance: same Clinical Uses: Mycobacterium avium, Strep throat Clinical Uses: Mycobacterium avium, Strep throat

and URI and some anaerobesand URI and some anaerobes Side Effects: GI upset and headache but less Side Effects: GI upset and headache but less

frequently than Erythromycinfrequently than Erythromycin Azithromycin (Zithromax)Azithromycin (Zithromax)

MOA: sameMOA: same Resistance: sameResistance: same Clinical Uses: combined erythro and clarithro. Clinical Uses: combined erythro and clarithro.

Used to treat same things and also uncomplicated Used to treat same things and also uncomplicated chlamydiachlamydia

Side Effects: GI upset and abdominal pain but less Side Effects: GI upset and abdominal pain but less frequently than erythrofrequently than erythro

Protein Synthesis InhibitorsProtein Synthesis Inhibitors LincosamidesLincosamides

Clindamycin (Celocin)Clindamycin (Celocin) MOA: binds to the 50s subunit and prevents MOA: binds to the 50s subunit and prevents

chain elongation by blocking transpeptidationchain elongation by blocking transpeptidation Resistance: alteration of ribosome binding site Resistance: alteration of ribosome binding site

and enzymatic inactivation of the drugand enzymatic inactivation of the drug Clinical Uses: covers gram + and most Clinical Uses: covers gram + and most

anaerobes. DOC for severe anaerobic GI anaerobes. DOC for severe anaerobic GI infectionsinfections

Side Effects: abdominal cramps, diarrhea, Side Effects: abdominal cramps, diarrhea, reversible LFT elevation, classically associated reversible LFT elevation, classically associated with pseudomembranous colitis (due to C. diff with pseudomembranous colitis (due to C. diff resistance)resistance)

Protein Synthesis InhibitorsProtein Synthesis Inhibitors Tetracycline, DoxycyclineTetracycline, Doxycycline

MOA: Inhibits protein synthesis by binding to MOA: Inhibits protein synthesis by binding to the 30s subunit and blocking amino-acid the 30s subunit and blocking amino-acid linked tRNA from binding to the A site of the linked tRNA from binding to the A site of the ribosomeribosome

Resistance: proteins that transport drugs out Resistance: proteins that transport drugs out of the cellof the cell

Clinical Uses: acne and chlamydia. Also used Clinical Uses: acne and chlamydia. Also used for Borrelia Burgdorferi (Lyme Disease)for Borrelia Burgdorferi (Lyme Disease)

Side Effects: GI distress, reversible Side Effects: GI distress, reversible nephrotoxicity, hepatotoxicity, nephrotoxicity, hepatotoxicity, photosensitivity, dental staining (gray line)photosensitivity, dental staining (gray line)