ANTIBIOTICS A brief overview for DMAT PA-1

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ANTIBIOTICSA brief overview for DMAT PA-1
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DEFINITIONS

• Antibiotic- agents derived from natural sources
  (bacteria or molds) used to treat infection by
  suppressing or destroying the causative
  microorganism
• Antimicrobial- those anti-infective agents which
  are derived from synthetic substances
• these two terms are now used interchangeably
• Antiseptic- an agent used to inhibit bacterial
  growth
• Bacteria- microscopic single-celled organisms
  containing DNA and cell walls
• Bactericidal- kills the bacteria
• Bacteriostatic- inhibits the growth of the
  bacteria
• Disinfectant- an agent used to kill bacteria
• Normal flora-non-pathogenic bacteria that live on
  human skin and mucous membranes
• Pathogen-bacteria that cause disease
• Spectrum of activity- a products range of
  antimicrobial activity

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CLASSIFICATION OF BACTERIA

• I. Shape
• Spherical (cocci)
• single cells (micrococci)
• pairs (diplococci)
• clusters (staphylococci)
• chains (streptococci)
• cubical groups (sarcinae)
• Rod-like (bacilli)
• oval shapes (coccobacilli)
• chains (streptobacilli)
• Spiral (spirochetes)
• rigid (spirilla)
• flexible (spirochetes)
• curved (vibrios)
• II. Stain
• (gram-stain)
• gram-positive (stains blue)
• gram-negative (stains pink)

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COMMON EXAMPLES

• Gram-positive aerobes
• streptococcus pneumoniae
• pericarditis,pneumonia,acute sinusitis,
  meningitis, otitis media, septicemia
• enterococcus faecalis
• burn wound sepsis, infective
  endocarditis
• staphylococcus aureus
• pneumonia, cellulitis, boils, toxic
  shock, postoperstive bone and joint infections,
  peritonitis, styes, suppurative conjunctivitis,
• staphylococcus epidermis
• human bites,burns,IV line infections,
  postoperative bone and joint infections
• bacillus anthracis
• anthrax
• corynebacterium diphtheriae
• pharyngitis, tonsilitis, diphtheria
• streptococcus agalactiae (group B
  streptococcus)
• bacterial sepsis and meningitis in
  newborns, endometritis and fever in postpartum
• streptococcus pyogenes (group A
  streptococcus)
• diabetic foot ulcers, pharyngitis,
  tonsilitis, burns, cellulitis, decubitus ulcers,
  impetigo, toxic shock, necrotizing fasciitis,
  scarlet fever, rheumatic fever
• Gram-positive anaerobes
• clostridium difficile

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• Gram-negative aerobes
  
  
  
  neisseria meningitidis
• meningitis
• escherichia coli
• urinary tract infections,
  pyelonephritis, septicemia, gastroenteritis,
  peritonitis
• neisseria gonorrhoeae
• gonorrhea, pelvic inflammatory
  disease
• pseudomonas aeruginosa
• puncture wounds, complicated
  urinary tract infections (catheter related),
  burns, pneumonia (ventilator related)
• haemophilus influenzae
• pneumonia, meningitis, otitis
  media, acute sinusitis
• moraxella catarrhalis
• pneumonia
• klebsiella pneumoniae
• wounds, otitis media,
  aspiration pneumonia
• legionella sp.
• Legionnaires disease
• shigella sp.
• severe diarrhea, gastroenteritis
• salmonella sp.

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CLASSIFICATION OF ANTIBACTERIAL AGENTS

• Aminoglycosides
• B-lactams
• Penicillins
• Cephalosporins
• Carbapenems
• Macrolides
• Quinolones
• Sulfonamides
• Tetracyclines
• Miscellaneous Agents
• Vancomycin
• Clindamycin
• Metronidazole
• Fluconazole
• Terconazole
• Miconazole
• Nystatin
• Rifaximin
• Nitrofurantoin

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AMINOGLYCOSIDES

• Miscellaneous facts bactericidal
• concentration-dependent
  killingthe bactericidal effect increases as the
  antibiotic concentration increases
• post-antibiotic effect
  continues to inhibit bacterial growth for
  several hours after aminoglycoside concentrations
  are no longer detectable
• higher doses at longer
  intervals
• often used in
  combination with B-lactam antibiotics to achieve
  antibacterial synergy to treat serious
  pneumococcal and enterococcal endocarditis
• no oral absorption
  must give IV/IM
• rapid renal excretion
• poor CNS penetration
• clinical differences
  among the agents are subtle
• Spectrumgram-negative enterobacteria
• no activity against
  anaerobes
• Therapeutic uses suspected sepsis, pneumonia,
  meningitis, complicated urinary tract infections,
  osteomyelitis, bacteremia, peritonitis
• Drawbacks very limited by their toxic potential
  
  
  
  ototoxic (irreversible) and nephrotoxic
  
• nephrotoxicity more
  common than ototoxicity, often reversible, most
  common in the elderly and those concurrently
  receiving amphotericin B, cephalosporins, or
  vancomycin
• accumulate in the
  proximal tubule of the kidney mild renal
  dysfunction occurs in 25 of patients on these
  drugs for several days or more
• once daily dosing has
  been reported to be effective and less
  nephrotoxic
• caution in patients
  with decreased renal function
• caution with other
  ototoxic and nephrotoxic drugs
• neuromuscular
  blockade can occur with high doses, rapid IV
  administration, in addition to neuromuscular
  blocking agents or anaesthetics, hypocalcemia,
  myasthenia gravis, and with blood transfusions

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• Gentamicin(Garamycin)IV/IM
• More active than tobramycin against serratia
  organisms (septicemia)
• Activity against mycobacterium and e.coli
• Used in combination with other antibiotics to
  treat staph. aureus and certain species of
  streptococcus
• Serum concentrations are unpredictable after IM
  administrationIV is the preferred route
• Gentamicin ophth soln (Garamycin)
• Potential ocular irritation and burning
• Tobramycin (Nebcin)IV/IM
• Better activity than gentamicin against
  pseudomonas aeruginosa (puncture wounds,urinary
  tract infections,burns, pneumonia)
• Some studies suggest it is less nephrotoxic than
  gentamicinnot firmly established
• Used in combination with other antibiotics to
  treat staph. aureus and certain species of
  streptococcus
• IV is the preferred route of administration
• Amikacin
• Kanamycin
• Neomycin
• Netilmicin
• Streptomycin
• Paromomycin

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B-LACTAMS

• Miscellaneous facts
• contain a unique 4 member ring that is
  essential for antibacterial activity
• certain bacteria produce and enzyme
  (B-lactamase) that breaks the ring and
  inactivates the antibiotic
• B-lactamase producing bacteris staph.
  Aureus
• 
  h. influenzae
• 
  bacteroides sp.
• 
  pseudomonas sp.
• 
  legionella sp.
  
  
• drug interaction with probenecidprobeneci
  d inhibits renal excretion of the antibiotics
  causing higher, prolonged serum levels
• anaphylactic reactions are common
• (urticaria, laryngeal
  edema,bronchospasm)
• Penicillins
• Cephalosporins
• Carbapenems
• 
  
• 
  
• 
  

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PENICILLINS

• Miscellaneous factsbactericidal
• 
  Four Subdivisions
• 
  Natural Penicillins
• 
  Aminopenicillins
• 
  Penicillinase-Resistant
  Penicillins
• 
  Extended-Spectrum
  Penicillins
• Spectrumbroad spectrum
• gram-positive
  and gram-negative
• Therapeutic usesoropharyngeal infections,
  sexually transmitted diseases, pharyngitis,
  otitis media, sinusitis, bacteremia, anthrax,
  skin and soft tissue infections, mild respiratory
  infections, uncomplicated urinary tract
  infections
• Drawbacks resistance
• 
  hypersensitivity reactions (occur in up to 10 of
  people receiving penicillins)
• bone
  marrow depression
• 
  gastrointestinal distress
• 
  potential to cause seizures when given in high
  doses to patients with renal dysfunction
• 
  ticarcillin and carbenicillin can cause platelet
  dysfunction

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NATURAL PENICILLINS

• Miscellaneous facts
• highly active against gram-positive cocci
  and gram-negative cocci
• most common use is for streptococcus sp.
• Penicillin G Sodium (Pfizerpen) IV/IM
• Penicillin VK (Veetids) oral
• Penicillin G procaine
• repository form IM use only
• Penicillin G benzathine
• repository form IM use only

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AMINOPENICILLINS

• Miscellaneous facts
• broad-spectrum penicillins
• their spectrum is similar to but broader
  than that of the natural and penicillinase-resista
  nt penicillins
• ineffective against most staphylococcal
  organisms
• commonly used for upper respiratory
  infections, uncomplicated urinary tract
  infections and otitis media
• Amoxicillin oral capsules suspension
• semisynthetic agent
• better absorption and less frequent
  dosing than ampicillin
• better bioavailability than
  penicillinmore stable to gastric acid
• Amoxicillin/clavulanic acid (Augmentin)oral
  chewables, tablets and suspension
• clavulanic acidno antibacterial
  activity, it inhibits B-lactamase by binding to
  it and inactivating it-therefore increasing the
  spectrum of activity of amoxicillin
• clavulanic acid causes a high incidence
  of gastrointestinal effects
• more effective than amoxicillin against
  staph. aureus, klebsiells sp., and bacteroides
  fragilis
• Ampicillin sodium IV/IM
• more effective than amoxicillin against
  shigellosis sp.

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PENICILLINASE-RESISTANT PENICILLINS

• Miscellaneous facts
• active against gram-positive aerobes
• limited activity against
  gram-negative and anaerobic bacteria
• are not inactivated by
  B-lactamase
• less potent than natural
  penicillins against organisms susceptible to
  natural penicillins cannot substitute for
  natural penicillins
• complete cross-resistance
  exists among the group
• all are identical except for
  their route of administration
• commonly used for bacteremia,
  skin and soft tissue infections, respiratory
  tract infections, bone and joint infections,
  urinary tract infections
• ineffective against MRSA/MRSE
• Dicloxacillin(Dynapen)oral capsule
  
  
  food decreases oral bioavailibilityadminis
  ter on an empty stomach
• Nafcillin(Nallpen)IM/IV
• semisynthetic
• metabolized by liver useful in patients
  with renal impairment
• associated with neutropenia in 10 to 20
  of patients
• multiple drug interactions
  (warfarin,etc.)
• Cloxacillin
• Methicillin
• Oxacillin

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EXTENDED-SPECTRUM PENICILLINS

• Miscellaneous facts
• also known as antipseudomonal
  penicillins
• have broadest spectrum of all
  penicillins
• used to treat serious infections
  caused by gram-negative aerobes
• ineffective against staphylococci sp.
• hypersensitivity reactions are more
  common in this subdivision
• all inhibit platelet aggregation
  result in bleeding
• Piperacillin
• Piperacillin/tazobactam (Zosyn)IV
• tazobactamno antibacterial activity,
  inhibits B-lactamase therefore enhancing the
  intrinsic activity of piperacillinincreased
  gastrointestinal side effects
• most potent extended-spectrum
  penicillin against pseudomonas sp.
• effective in treatment of nosocomial
  pneumonia
• Ticarcillan
• Ticarcillin/clavulanic acid

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CEPHALOSPORINS

• Miscellaneous facts
• B-lactam antibiotics
• bactericidal
• 4 generations
• classified according to their
  spectrum of activity
• each generation increases its
  gram-negative activity but, loses activity
  against gram-positive organisms
• popular due to their low
  toxicity and activity against serious infections
• Spectrum gram-positive and gram-negative
• no activity against MRSA
• Therapeutic usesperioperative prophylaxis,
  urinary tract infections, acute otitis media,
  sinusitis, etc
• Drawbacks most are eliminated via renal
  excretionadjust dosages in renal insufficiency
  
  
  hypersensitivity reactions (fever, maculopapular
  rash, anaphylaxis, hemolytic anemia)
  
  
  gastointestinal effects
  
  hypoprothrombinemia
• potential for nephrotoxicity
• cross-sensitivity with penicillins in up to
  10 of patients receiving cephalosporins

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1st GENERATION CEPHALOSPORINS

• Miscellaneous facts
• oldest cephalosporins
• gram-positive activity basic
  gram-negative activity (except enterococci)
• widely used for perioperative
  prophylaxis
• used to treat klebsiella sp.,
  skin and soft tissue infections, respiratory
  tract infections, otitis media
• Cefazolin(Ancef)IM/IV
• compared to other 1st generation
  cephalosporins it achieves higher blood levels
  after administration, has greater gram-positive
  coverage and requires less frequent dosing
• Cephalexin(Keflex) oral capsules ,oral
  suspension
  primarily used for
  otitis media and respiratory tract infections
• Cephadroxil
• Cephradine

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2nd GENERATION CEPHALOSPORINS

• Miscellaneous facts
  
  less gram-positive coverage more
  gram-negative coverage than 1ST generation
  cephalosporins
• also active against B-lactamase producing
  strains of haemophilius influenzae
• Cefaclor
• Cefoxitin
• Cefprozil
• Cefuroxime
• Cefotetan

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3rd GENERATION CEPHALOSPORINS

• Miscellaneous facts
• increased gram-negative coverage
  decreased gram-positive coverage over 2nd
  generation cephalopsorins
• best CNS penetration of all
  cephalosporinsvery valuable in treatment of
  meningitis caused by meningococci, pneumococci,
  haemophilus influenzae, and enteric gram-negative
  bacilli
• especially useful for gram-negative upper
  respiratory tract infections, otitis media,
  urinary tract infections and skin infection
  
  
  
  empiric therapy for life-threatening infections
  in which resistant organisms are the most likely
  cause
  
  
  treatment of sepsis of unknown origin in
  immunosuppressed patients
  
  initial therapy in mixed bacterial infections
• Cefotaxime(Claforan)IM/IV
  
  
  commonly used to treat empiric
  gram-negative meningitis, serious bacteremias,
  pneumonia, and community-acquired infections
• Ceftriaxone(Rocephin)IM/IV
• longest half-life of all cephalosporins
  allowing for once daily dosing
• DOCneisseria gonorrhoeae
• Cefdinir
• Cefixime
• Cefoperazone
• Cefopodoxime proxetil
• Ceftazidime
• Ceftibuten
• Ceftizoxime
• Cefditoren

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4th Generation Cephalosporins

• Miscellaneous facts
• newest cephalosporins
  
  same coverage as 3rd
  generation cephalosporins with additional
  coverage against pseudomonas sp
• high degree of resistance to B-lactamase
  producing organisms
• good activity against organisms that are
  resistant to 3rd generation cephalosporins
• commonly used for febrile neutropenic
  patients
• Cefepime (Maxipime)

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CARBAPENEMS

• Miscellaneous facts
• B-lactam antibiotics
• bactericidal
• Spectrumgram-positive cocci, gram-negative rods,
  and anaerobes
• broader spectrum than most
  B-lactams
• Therapeutic usesurinary tract infections, lower
  respiratory tract infections, gangrene, sepsis,
  pneumonia,intra-abdominal infections,
  gynecological infections, etc.
• Drawbacks anaphylactic reactions, seizures,
  confusion, dizziness, gastrointestinal issues
• Imipenem/cilastatin
• Ertapenem
• Meropenem

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MACROLIDES

• Miscellaneous facts
• mostly bacteriostaticcan be bactericidal
• newer macrolides-better absorption and
  less gastrointestinal effects
• Spectrum gram-positive cocci and bacilli
  some gram-negative cocci
• mycoplasma pneumoniae, chlamydia
  trachomatis, legionella sp., corynebacterium
  diphtheriae, campylobacter sp., treponema
  pallidum, propionibacterium acnes, borrelia
  burgdorferi
• DOCgroup A streptococcal and pneumococcal
  infections when penicillin cannot be used
• Therapeutic uses
  
  Legionnaires
  disease, dental prophylaxis , chlamydial
  infections, ance, diphtheria, pertussis, ocular
  infections
• Drawbacks
• numerous drug interactions erythromycin
  inhibits the hepatic metabolism of other drugs
  (theophylline, digoxin, corticosteroids,
  carbamazepine, cyclosporin, lovastatin, etc.)
• cardiac issuescauses QT prolongation and
  torsade de pointes
• gastrointestinal disturbances
  (dose-related),skin rashes, eosinophilia,
  tinnitus, dizziness, reversible hearing loss

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• Erythromycin base (ERYTAB) oral tablet
  
  
  
  enteric coated,
  delayed-release tabs (do not crush)
• DOCLegionnaires disease, mycoplasma
  pneumonia and chlamydial infections
• drug interactions with terfenadine,
  astemizole, pimozide, etc.
  
  
  dose must be decreased
  with decreased liver function
• pregnancy category B
  
  
  
  Erythromycin
  ethylsuccinate(EES) oral suspension
• Erythromycin ophth oint.
• superficial ocular infections
• prophylaxis of neonatal ophthalmia due
  to neisseria gonorrhoeae or chlamydia trachomatis
• Azithromycin(Zithromax, Z-Pak) oral
  suspension,oral tablets
• semisynthetic macrolide
• less active than erythromycin against
  gram-positive organisms
• more active than erythromycin against
  haemophilus influenzae and other gram-negative
  organisms
• concentrates in cells tissue levels are higher
  than serum levelsincreased efficacy and duration
  of action-less tendency to cause drug
  interactions
• once daily dosing
  
  
  
  less
  gastrointestinal issues than with other
  macrolides
• very useful in nongonococcal urethritis
  caused by chlamydia, lower respiratory tract
  infections, mycobacterium avium complex
  infection, pharyngitis, pelvic inflammatory
  disease, nongonococcal urethritis caused by
  chlamydia, Legionnaires disease
• pregnancy category B
• Clarithromycin(Biaxin) XL oral tablets, oral
  suspension semisynthetic macrolide
• same spectrum as erythromycin more potent
• enhanced activity against haemophilus influenzae
  and mycobacterium avium complex

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QUINOLONES

• Miscellaneous facts
• bactericidal (concentration dependent)
• 4 generations each generation adds
  coverage for a new group of pathogens
• different mechanism of action --
  thus, no cross resistance with other classes of
  antibiotics
• produce a false-positive urine
  screening result for opiates when using a
  commercially available immunoassay kit
• Spectrum highly active against gram-negative
  aerobes gram-positive activity
• no activity for most anaerobes
• Therapeutic uses
• urinary tract infections, lower
  respiratory tract infections, sinusitis, otitis
  media, infectious diarrhea, prostatitis, empiric
  use in febrile neutropenic patients
• Drawbacks
• relatively free of side effects and
  toxicity
• phototoxicity
• not recommended in children under 18 years
  of age (cartilage malformations were found in
  studies in immature animals),tendon rupture,
  cardiac QT prolongation( associated with 2nd and
  3rd generations), CNS stimulation, hypoglycemia,
  seizures, anaphylactic reactions,
  pseudomembraneous colitis, can cause exacerbation
  of myasthenia gravis
  multiple drug interactions theophylline,
  antacids, iron, multivitamins, warfarin, NSAIDs
  (potential to increase risk of seizure),
  antiarrhythmic drugs
• pregnancy category C

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1st GENERATION QUINOLONES

• Miscellaneous facts
  bactericidal
• gram-negative coverage (excluding
  pseudomonas)
  
  limited use due to the development of bacterial
  resistance
• poor oral availability limits its systemic
  use
• common uses include urinary tract
  infections
• Nalidixic acid

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2nd GENERATION QUINOLONES(FLUOROQUINOLONES)

• Miscellaneous facts
• bactericidal
• increased gram-negative coverage
  (including pseudomonas), gram-positive cocci, and
  mycobacteria
• addition of fluorine ion to the
  quinolone structure fluoroquinolones
• QT prolongation and torsade de pointes
• Ciprofloxacin (cipro)oral tablets/IV
• good penetration into boneuseful in
  osteomyelitis
• urinary tract infections, lower
  respiratory tract infections, sinusitis, empiric
  use in febrile neutropenia, typhoid fever,
  infectious diarrhea, prostatitis, bacterial
  conjunctivitis, corneal ulcers, nosocomial
  pneumonia
• indicated for use in mycobacterium avium
  complex in patients with AIDS

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2nd GENERATION QUINOLONES(FLUOROQUINOLONES)

• used in combination with other drugs to
  treat multi-drug-resistant tuberculosis
• most potent flouruquinolone against
  pseudomonas aeruginosa
• no longer drug of choice for neisseria
  gonorrhoeae (becoming resistant)
• absolute contraindication tendon pain,
  tendon rupture, tendonitis
• oral dosage
  equivalent IV dosage
• 250mg q12h
  200mg IV q12h
• 500mg q12h
  400mg IV q12h
• 750mg q12h
  400mg IV q8h
• Ofloxacin (Floxin,Ocuflox)
• oral/ophth/otic use
• less potent than ciprofloxacn against most
  gram-negative bacteria
• most active 2nd generation against
  chlamydia trachomatis
• Norfloxacin (Noroxin, Chibroxin)

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3rd GENERATION QUINOLONES(FLUOROQUINOLONES)

• Miscellaneous facts
  
  
  QT prolongation
  
  
  bactericidal
• extended gram-positive coverage
  (particularly against penicillin-sensitive and
  penicillin-resistant streptococcus pneumoniae,
  mycoplasma pneumoniae chlamydia pneumoniae)
• gram-negative coverage (including pseudomonas
  sp.)
• decrease dosage in renal impairment
• treatment of community-acquired
  pneumonia, acute sinusitis, acute exacerbations
  of chronic bronchitis, bacterial conjunctivitis
• Gatifloxacin
• ophthalmic, bacterial conjunctivitis
• Levofloxacin
• oral, IV, ophthalmic
• less QT prolongation than with other
  fluoroquinolones
• Moxifloxacin
• oral,IV, ophthalmic
• not used for urinary tract infections
• approved for treatment of complicated
  intra-abdominal infections

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4th GENERATION QUINOLONES(FLUOROQUINOLONES)

• Miscellaneous facts
• bactericidal
• gram-positive gram-negative
• significant coverage against
  anaerobes
• Trovafloxacin (Trovan)
• restricted by FDA to serious
  life-or-limb-threatening infections due to
  serious drug induced hepatic adverse effects
• BLACK BOX WARNING
• treatment restriction limitationshospita
  ls and long term care facilities
• liver injury leading to liver
  transplantation and or death

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SULFONAMIDES

• Miscellaneous facts
  
  
  bacteriostatic
• Spectrum mostly gram-positive, some
  gram-negatives
• also activity against certain strains of
  chlamydia trachomatis, nocarida, actinomyces,
  bacillus anthracis
• Therapeutic uses animal and human bites, urinary
  tract infections, otitis media, chronic
  bronchitis, travelers diarrhea, sexually
  transmitted bacterial infections, ocular
  infections and burns
• Drawbacksphotosensitivity, can cause
  Stevens-Johnson syndrome, hypersensitivity
  reactions, blood dyscrasias, caution in patients
  with G6PD deficiency (can cause acute hemolysis),
  crystalluria, hematuria
• drug interactions with phenytoin, oral
  anticoagulants, sulfonylureas
• cross-allerginicity between the individual
  sulfonamides
• discontinue at first sign of skin rash or
  other reaction
• SMZ/TMP(Bactrim,BactrimDS)
• (sulfamethoxazole/trimethoprim)-gtsynergistic
  combination
• bacteriostatic-in combination with
  trimethoprimbactericidal
• DOCtreatment and prophylaxis of
  pneumocystis carinii
• useful in acute gonococcal urethritis, acute
  exacerbation of chronic bronchitis
• Sodium Sulfacetamide 10 ophth soln
• Used to treat conjunctivitis or superficial
  bacterial eye infections,corneal ulcers
• can cause a delay in corneal wound
  healing
• local irritation, burning, stinging
• Silver sulfadiazine1 cream(Silvadene)
• bactericidal

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TETRACYCLINES

• Miscellaneous uses
• bacteriostatic
• cross-resistance with the group is
  extensive
• Spectrum gram-negative gram-positive
• broad spectrum
  agentscoverage includes spirochetes, rickettsia,
  mycoplasma pneumonia, chlamydia sp., certain
  protozoa species
• Therapeutic uses
  
  
  DOCrickettsial (Rocky Mountain Spotted Fever),
  chlamydial, mycoplasmal infections, anthrax
  
  frequently
  used for acne and periodontitis
• useful alternative to penicillin in
  treatment of anthrax, syphilis, gonorrhea, Lyme
  disease, and h. influenzae respiratory infections
• Drawbacks photosensitivity
  
  gastrointestinal
  distress, hypersensitivity reactions, hepatoxic
  (especially in pregnant women), pregnancy
  category D, tooth discoloration (binds to calcium
  in teeth bones-enamel hypoplasia can also
  occur), not recommended in childrenlt8 years old,
  cannot give with antacids or milk, cannot use
  tetracycline after expiration date(causes renal
  tubular dysfunction which can lead to renal
  failure), take with fluids to avoid esophageal
  irritation
• Doxycycline (Vibramycin) oral tablets
• excreted mainly in feces very useful in
  patients with poor renal function
• Minocycline
• Tetracycline

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MISCELLANEOUS AGENTS

• Vancomycin (Vancocin)IV peaks20-40mcg/ml
• Miscellaneous facts bactericidal
  
  troughs5-15mcg/ml
• very useful in patients
  allergic to penicillins or cepphalosporins
• Spectrum gram-positive organisms including
  MRSA/MRSE and enterococci
• Therapeutic usesserious infectionsendocarditis,
  osteomyelitis, staphylococcal pneumonia,
  treatment of pseudomembranous colitis caused by
  c.difficile or s.aureus enterocolitis
• oral form used only for c. difficile
• Drawbacks ototoxicit y
  
  
  
  increased ototoxicity
  nephrotoxicity when given with other ototoxic and
  nephrotoxic drugs
• monitor blood levels
  
  
  
  
  hypersensitivity reactions
  
  
  
  facial
  flushing and hypotension with too rapid infusion
  of the drug (red man syndrome)
• Clindamycin (Cleocin)oral/IV/IM
• Miscellaneous facts bacteriostatic
  
  
  
  cross resistance with
  macrolides is common
• reserve for serious infections in
  patients with penicillin allergies
• does not diffuse into cerebrospinal
  fluiddo not use for meningitis
• Spectrummost gram-positive many anaerobic
  organisms
• bacteroides fragilis
• Therapeutic uses skin, respiratory tract, and
  soft tissue infections caused by staphylococci,
  pneumococci, and streptococci, dental infections,
  acne, bone joint infections, bacterial
  vaginosis
• Drawbacks limited by its toxicities
  
  
  
  
  gastrointestinal issues, blood dyscrasias,
  Stevens-Johnson syndrome
  
  
  dose must be
  decreased with impaired hepatic function
  
  
  potentiates
  the effects of neuromuscular blocking agents
• BLACK BOX WARNING
• first antibiotic to be associated with
  pseudomembraneous colitis
• c. difficile associated diarrhea
  (pesudomembranous colitis)

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• Metronidazole(Flagyl) oral/IV
• Miscellaneous factsantibacterial and
  antiprotozoal agent
• 
  amebicideamebicidal and trichomonacidal
• Spectrumanaerobic gram-positive and anaerobic
  gram-negative
• certain protozoan parasites
  (trichomonas vaginalis, entamoeba histolyticass,
  giardia lamblia,etc.)
  
  DOCc.difficile, bacterial
  vaginosis (gardnerella vaginalis), c. tetani
• Therapeutic usesamebic dysentery, giardiasis,
  trichomoniasis, intra-abdominal, pelvic, soft
  tissue, periodontal, and odontogenic infections,
  lung abscess, acne, meningitis, bacterial
  septicemia, lower respiratory tract infections,
  endocarditis
• Drawbacks hepatic metabolism-dosage adjustment
  in patients with liver dysfunction
• gastrointestinal distress, headache, dark
  coloration of urine, leukopenia, dizziness,
  ataxia disulfiram-like reaction with ethanol
  
  
  inhibits warfarin
  metabolism-increased bleeding
  
  
  metallic taste
• use cautiously in pregnancy (avoid in
  first trimester)
• drug interactions warfarin, phenytoin,
  phenobarbital, cimetidine, lithium, etc.
• absolute contraindication in breast
  feeding
  
  
  use with caution in patients with evidence
  of or history of hematological disease
• Fluconazole(Diflucan) oral tablet
• Miscellaneous facts azole antifungal agent
  
  
  
  fungistatic
• Spectrumactive against many fungi, including
  yeasts, dermatophytes, actinomycegtes, and some
  phycomycetes, cryptococcus, candida, aspergillis
• Therapeutic usesvaginal candidiasis,
  oropharyngeal and esophageal candidiasis,
  systemic candida infections and cryptococcal
  meningitis
• DOCcryptococcal meningitis
• Drawbacksgastrointestinal disturbances, skin
  rashes, hepatic necrosis, Stevens-Johnson
  syndrome, anaphylaxis, alopecia
  multiple drug
  interactions phenytoin, cyclosporine,
  warfarin,sulfonylureas, etc
  
  pregnancy
  category C

33

• Terconazole cream (vaginal)
• Miscellaneous facts fungicidal
• Spectrumcandida albicans
• active against dermatophytes, yeasts, and at high
  concentrations gram-positive gram-negative
  bacteria
• Therapeutic uses complicated and uncomplicated
  vulvovaginal candidiasis
• Drawbacks pruritis, irritation-vulvovaginal
  burning, headache, body pain
  
  
  pregnancy category C (not
  recommended during first trimester)
• Miconazole cream 2
  
  Miscellaneous facts imidazole
  antifungal agent
  
  
  fungistatic
  
  
  
  
  topical or intravaginal use
• Spectrumbroad spectrum
  
  
  
  blastomyces
  dermatitidis, candida sp., cryptococcus
  neoformans, coccidioides immitis, histoplasma
  capsulatum, paracoccidioides brasiliensis,
  sporothrix schenckii
• Therapeutic uses for topical and vaginal fungal
  infections
  
  
  (vaginal candidiasis,
  tinea infections, cutaneous candidiasis)
• Drawbacks pregnancy category C
• Nystatin cream
• Miscellaneous facts antifungal agent
• fungicidal and fungistatic
• Spectrum primary activity against candida sp.
  
  
  
  
  ineffective against bacteria, protozoa,
  trichomonads, and viruses
• Therapeutic uses treatment of oropharyngeal,
  cutaneous, mucocutaneous and vulvovaginal
  candidiasis
• poor oral absorption, good
  local activitygreat choice for oral and
  esophageal candida infections
• Drawbacks oral form causes gastrointestinal
  distress

34

• Rifaximin(Xifaxan) oral tablets
• Miscellaneous facts rifamycin antibiotic
• non-systemically
  absorbed-no significant drug interactions
• Spectrum gram-positive, gram-negative, aerobes,
  anaerobes
• Therapeutic uses Travelers diarrhea caused by
  non-invasive strains of e.coli
• Drawbacks do not administer to patients with
  diarrhea complicated by fever or blood in the
  stools
• flatulence, headache,
  abdominal pain, nausea, constipation, pyrexia
• caution in patients allergic
  to any of the rifamycin antimicrobial agents
• not for use in children under
  12 years of age
• pregnancy category Cif
  necessaryonly in 2nd and 3rd trimesters
• poor GI absorption-no
  systemic bioavailability-no drug interactions
• 200mg tid for 3 days
• Loperamide(Imodium) oral capsules
• Miscellaneous facts synthetic antidiarrheal for
  oral use
  
  
  prolongs transit time of the
  intestinal contents (decreases peristalsis),
  reduces daily fecal volume, increases viscosity
  and bulk density---diminished loss of fluids and
  electrolytes
• Spectrum

35

• Nitrofurantoin
• Miscellaneous facts bacteriostatic-can be
  bactericidal in high concentrations
  
  
  urinary tract antiseptic/bladder
  antiseptic
• concentrates in the renal tubules and bladder
  doesnt achieve blood levels high enough to treat
  systemic infections
• Spectrumgram-positive and gram-negative
• Therapeutic usesprevention and treatment of
  uncomplicated urinary tract infections caused by
  escherichia coli or staphylococcus saprophyticus
• Drawbacksgastrointestinal issues fairly common
  
  
  
  hypersensitivity reactions, headache, vertigo,
  dizziness
• polyneuropathy ---with high doses or
  patients with renal impairment
  
  
  
  monitoring
  parameters BUN, CrCl, LFTs
• Mebendazole (vermox) oral tablet
• Miscellaneous facts anthelmintic
  
  
  
  death of the worm is slowcomplete
  gastrointestinal clearance up to 3 days after
  therapy
• retreatment necessary if patient not
  cured in 3 weeks
• Spectrum ancylostoma duodenale (hookworm)
• ascaris lumbricoides
  (roundworm)
• enterobius vermicularis
  (pinworm)
• necator americanus (American
  hookworm)
• trichuris trichiura (whipworm)
• Therapeutic uses DOC GI hematodes

36

• Bacitracin ointment
• Miscellaneous facts bacteriostatic potential to
  be bactericidal
• Spectrum gram-positive bacteria
• Therapeutic uses topical use to prevent
  superficial skin infections following minor
  injuries on small areas of the body
• Drawbacks caution in patients with neomycin
  hypersensitivity
• maximum duration of use 7
  days
• incidence of contact
  dermatitis is about 2
• Triple antibiotic ointment
• Miscellaneous facts (neomycin/polymyxin
  B/bacitracin)
• Spectrum gram-positive and gram-negative
  
  (neomycin polymyxin B both have gram-negative
  coverage)
• Therapeutic uses superficial skin infections
• Drawbacks can cause allergic dermatitis
  
  neomycin containing products can cause
  allergic reactions in about 1 in 20 people

37

• Neomycin/polymyxin/hc otic susp
• Miscellaneous facts antibacterial
  anti-inflammatory
• Spectrumgram-negative aerobes
• MRSA coverage
• Therapeutic uses superficial bacterial
  infections of the external auditory canal
• maximum use 10
  days
• Drawbacks caution in patients with tympanic
  membrane perforation or chronic otitis media
  risk of ototoxicity
• allergic skin reactions
• pregnancy category c

38
QUIZ

• 1.Which antibiotic is associated with red man
  syndrome?
• A.) clindamycin
• B.) vancomycin
• C.) penicillin
• D.) ciprofloxacin
• 2.Which injectable cephalosporin is the drug of
  choice for neisseria gonorrhea?
• A.) Ancef
• B.) Rocephin
• C.) Claforan
• D.) Mefoxin
• 3. Why should you not use tetracycline after the
  expiration date?
• A.) renal failure
• B.) hepatic failure
• C.) QT prolongation
• D.) diarrhea
• 4.Which antibiotic is not included in the DMAT
  cache?
• A.) Rocephin
• B.) Amoxicillin
• C.) Levaquin

39
References

• Lacy C, Armstrong L,Goldman M, Lance L,
  Lexi-Comps Drug Information Handbook, 15th
  edition, 2007
• Beers M, Porter R, Jones T, Kaplan J, Berkwits M,
  The Merck Manual,18th edition, 2006
• Shargel L, Mutnick A, Souney P, Swanson L,
  Comprehensive Pharmacy Review, 6th edition, 2007
• Gilbert D,Moellering R, Eliopoulos G, Chambers H,
  Saag M, The Sanford Guide To Antimicrobial
  Therapy 2009 (39th edition), 2009
• Trevor A, Katzung B, Masters S, Pharmacology
  Examination and Board Review, 8th edition, 2008
• Clinical Pharmacology, online version, _at_
  www.clinicalpharmacology.com
• Epocrates Online, online version _at_
  www.epocrates.com
• Doxycycline hyclate capsules package insert.
  Eatontown, NJ West-ward Pharmaceutical Corp.
  2006 July
• Fluconazole tablets package insert. Miami, Fl
  Ivax Pharmaceuticals, Inc.2006
• Azithromycin tablets package insert. Peapack,
  NJGreenstone Ltd.2007 August
• Clarithromycin package insert. Jerusalem, Israel
  Teva Pharmaceutical IND. LTD 2008 Jan
• Erythromycin Base Filmtab package insert.
  Chicago,Il.Abbott Laboratories 2004 Nov
• Nystatin package insert. Ontario, Canada Taro
  Pharmaceuticals Inc.2005 June
• Erythromycin ophth. Ointment package insert.
  Melville, NYE.Fougera Co.1999
• Metronidazole tablets package insert.Pomona NY
  Pliva Krakow Pharmaceutical Company2007 May
• Ciprofloxacin package insert. Miami,Fl.Ivax
  Pharmaceuticals Inc2007 Feb
• Terconazole vaginal cream package
  insert.Hawthorne NYTaro Pharmaceuticals 2003
  July
• Dicloxacillin sodium package insert. Toronto,
  Canada. Novopharm Limited2006 Jan
• Nitrofurantoin capsules package insert.
  Morgantown, Wv Mylan Pharmaceuticals 2004
  August