Antimicrobials Flashcards
Gentamicin
Class: Aminoglycosides
TD: 1-2.5 mg/kg/dose
EID: 4-7mg/kg/dose
IV, IM, ophthalmic, topical
Renal: Q8H (CrCl >60), Q12H (40-60), Q24H (20-40), or PRN (
Tobramycin
Class: Aminoglycosides
TD: 1-2.5 mg/kg/dose
EID: 4-7mg/kg/dose
IV, IM, ophthalmic, inhaled (TOBI)
Renal: Q8H (CrCl > 60), Q12H (40-60), Q24H (20-40), PRN (
Streptomycin
Class: Aminoglycosides
Dosing: 15 mg/kg IM Q24H (max 1g)
25-30 mg/kg IM 2-3x Qwk
(max 1.5g)
Renal: Q24-72H (CrCl 10-50), Q72-96H
(
Amikacin
Class: Aminoglycosides
TD: 5-7.5 mg/kg/dose
EID: 15-20 mg/kg/dose
IV, IM
Renal: Q8H (CrCl >60), Q12H (40-60), Q24H (20-40), PRN (
Natural Penicillins
MOA: inhibit transpeptidation of cell walls by binding PBPs
Time-dependent killing (t/AUC)
Bactericidal (except Enterococci)
Coverage: Strep (DOC for Group A), some Enterococcus, PO anaerobes, Syphilis; minor Staph (
Penicillin V
Pen VK
Class: Natural Penicillins
Dosing: 125-500 mg PO Q6H
Tablet, suspension
Renal dose adjustment
SE: hypersensitivity (inc. anaphylaxis), GI upset, taste disturbance, rash, BMS, AIN, C.diff infection, seizures (accumulation)
Tablet taken on empty stomach
Suspension should be refrigerated
Aminoglycosides
MOA: 30S & 50S subunit binding that inhibits protein synthesis
Concentration-dependent killing
Peak/AUC
Bactericidal
Coverage: Gm (-) species; Gent/Strepto provide synergy for Gm (+) infections when combined with Beta lactams or Vanc
BBW: neurotoxicity, nephrotoxicity, fetal harm (Category D)
Monitoring: Hartford Nomogram (extended interval dosing)
Penicillin G
Benzathine (Bicillin L-A) & Procaine (Bicillin C-R)
Class: Natural Penicillins
Dosing: 1.2-2.4 MU IM
Frequency varies on indication
Renal dose adjustment
SE: hypersensitivity (inc. anaphylaxis), GI upset, rash, BMS, AIN, C.diff infection, seizures (accumulation)
BBW: can cause cardiorespiratory arrest or death if given IV
Penicillin G (Aqueous)
Pfizerpen-G
Class: Natural Penicillins
Dosing: 2-4 MU IV Q4-6H
Renal dose adjustments
SE: hypersensitivity (inc. anaphylaxis), GI upset, rash, BMS, AIN, C.diff infection, seizures (accumulation)
Aminopenicillins
MOA: inhibits transpeptidation of cell walls by binding PBPs
Time-dependent killing (t/AUC)
Bactericidal (except Enterococci)
Coverage: Strep, Enterococcus (DOC), Listeria, and limited Gm (-)
No MSSA, Klebsiella,
Moraxella, or SPICE A
E. faecium usually resistant
Pregnancy Category B
Amoxicillin
Amoxil, Trimox, Moxatag
Class: Aminopenicillins
Dosing: 250-500 mg PO Q8H
500-875 mg PO Q12H
775 mg XR PO Q24H
Tablet, chewable, capsule, suspension
Renal dose adjustments
DOC: AOM, H. pylori, IE ppx
SE: hypersensitivity (inc. anaphylaxis), taste disturbance, GI upset, rash, BMS, AIN, C.diff infection, seizures (accumulation)
PO suspension refrigerated for taste; stable 14D at RT
Moxatag taken w/in 1 hour of meal end
PO bioavailability 75-90%
Amoxicillin/Clavulanate
Augmentin, Augmentin XR, Amoclan
Class: Aminopenicillin/Beta-lactamase
Coverage: anaerobes
No SPICE A
Dosing: 500 mg PO TID
875 mg PO BID
2g XR PO BID
Tablet, chewable, suspension
Renal dose adjustment
SE: hypersensitivity (inc. anaphylaxis), taste disturbances, GI upset, rash, BMS, AIN, C.diff infection, seizures (accumulation)
CI (XR only): hx of cholestatic jaundice, hepatic dysfunction, or CrCl
Ampicillin
Class: Aminopenicillins
Dosing: 250-500 mg PO Q6H
1-2g IV Q4-6H
IV, IM, capsule, suspension
Renal dose adjustment
SE: hypersensitivity (inc. anaphylaxis), taste disturbance, GI upset, rash, BMS, AIN, C.diff infection, seizures (accumulation)
PO on empty stomach (1H prior/2H after)
IV only compatible in NS; stable at RT for 8H
Ampicillin/Sulbactam
Unasyn
Class: Aminopenicillin/Beta-lactamase Inhibitor
Coverage: anerobes, Acinetobacter
No SPICE
Dosing: 1.5-3G IV Q6H
Renal dose adjustment
SE: hypersensitivity (inc. anaphylaxis), GI upset, rash, BMS, AIN, C.diff infection, seizures (accumulation)
Only compatible in NS
Antistaphylococcal Penicillins
MOA: inhibits transpeptidation in cell walls by binding PBPs
Time-dependent killing (t/AUC)
Bactericidal (except Enterococci)
Coverage: MSSA (DOC) & Strep
No MRSA or Coag (-) Staph
Pregnancy Category B
Nafcillin
Class: Antistaphylococcal Penicillins
Dosing: 1-2g IV/IM Q4-6H
IV, IM
No renal dosing adjustment
SE: hypersensitivity (inc. anaphylaxis), GI upset, rash, hepatitis/increased LFTs, BMS, AIN, C.diff infection, seizures (accumulation)
Most tolerated in class (better for long-term therapy)
Vesicant (tx: hyaluronidase & cold packs)
Oxacillin
Class: Antistaphylococcal Penicillins
Dosing: 250-2000 mg IV Q4-6H
No renal dose adjustment
SE: hypersensitivity (inc. anaphylaxis), GI upset, rash, hepatitis/increased LFTs, BMS, AIN, C.diff infection, seizures (accumulation)
Dicloxacillin
Class: Antistaphylococcal Penicillins
Dosing: 125-500 mg PO Q6H
No renal dose adjustment
SE: hypersensitivity (inc. anaphylaxis), GI upset, taste disturbances, rash, hepatitis/increased LFTs, BMS, AIN, C.diff infection, seizures (accumulation)
Ureidopenicillins
&
Carboxypenicillins
MOA: inhibit transpeptidation of cell walls by binding PBPs
Time-dependent killing
Bactericidal (except Enterococci)
Coverage: MSSA, Strep, Gm (-) organisms inc. SPICE A, anaerobes (d/t beta-lactamase inhibitors)
Pregnancy Category B
Piperacillin/Tazobactam
Zosyn
Class: Ureidopenicillin/Beta-lactamase
Coverage: anerobes, SPICE A
No MRSA, VRE, Coag (-) Staph,
atypicals (CML), ESBLs
Dosing: 3.375-4.5g IV Q6-8H
Extended infusion dosing
Renal dose adjustment
SE: hypersensitivity (inc. anaphylaxis), GI upset, rash, BMS, AIN, C.diff infection, seizures (accumulation)
Ticarcillin/Clavulanic Acid
Timentin
Class: Carboxypenicillin/Beta-lactamase Inhibitor
Coverage: anerobes, Stenotropomonas, SICE A
No Pseudomonas or
Enterococci
Dosing: 3.1g IV Q4-6H
SE: hypersensitivity (inc. anaphylaxis), GI upset, rash, BMS, AIN, C.diff infection, seizures (accumulation)
Penicillin Drug Interactions
Probenecid: reduced PCN renal elimination
Methotrexate: increased [MTX]
Tetracyclines (& bacteriostatic agents): reduced PCN effectiveness by slowing bacterial growth
Mycophenolate: reduced active metabolites d/t impaired enterohepatic recirculation
Warfarin: increased INR (except Dicloxacillin & Nafcillin)
1st Generation Cephalosporins
MOA: inhibit transpeptidation of cell walls by binding PBPs
Time-dependent killing (t/AUC)
Bactericidal
Coverage: MSSA, minor Strep, Proteus, E.coli, Klebsiella (PEK)
BBW: PCN cross-reactivity
Pregnancy Category B
Cefadroxil
Class: 1st Generation Cephalosporins
Dosing: 500-1000 mg PO Q12H
Renal dose adjustment
SE: hypersensitivity (inc. anaphylaxis), GI upset, drug fever, rash, BMS, AIN, C.diff infection, seizures (accumulation)
Cefazolin
Ancef, Kefzol
Class: 1st Generation Cephalosporins
DOC for severe MSSA infections in PCN allergic patients
Dosing: 1-1.5g IV/IM Q8H
Renal dose adjustment
SE: hypersensitivity (inc. anaphylaxis), GI upset, drug fever, rash, BMS, AIN, C.diff infection, seizures (accumulation)
Cephalexin
Keflex
Class: 1st Generation Cephalosporins
Dosing: 250-1000 mg PO Q6H
Renal dose adjustment
SE: hypersensitivity (inc. anaphylaxis), GI upset, drug fever, rash, BMS, AIN, C.diff infection, seizures (accumulation)
2nd Generation Cephalosporins
MOA: inhibit transpeptidation of cell walls by binding PBPs
Time-dependent killing (t/AUC)
Bactericidal
Coverage: MSSA, Strep, Haemophilus, Neisseria (HNPEKS)
BBW: PCN cross-reactivity
Pregnancy Category B
Cefaclor
Class: 2nd Generation Cephalosporins
Dosing: 250-500 mg PO Q8H
Renal dose adjustment
SE: hypersensitivity (inc. anaphylaxis), GI upset, drug fever, rash, BMS, AIN, C.diff infection, seizures (accumulation)
Cefotetan
Class: 2nd Generation Cephalosporins
Coverage: anaerobes (B. fragilis has high resistance rates), reduced Gm (+)
Dosing: 1-2g IV/IM Q12H
Renal dose adjustment
SE: hypersensitivity (inc. anaphylaxis), GI upset, drug fever, rash, BMS, AIN, C.diff infection, seizures (accumulation)
N-methylthiotetrazole (NMTT) side chain causes hypoprothrombinemia & disulfiram-like reaction
Cefoxitin
Class: 2nd Generation Cephalosporins
Coverage: anaerobes, reduced Gm (+)
Dosing: 1-2g IV/IM Q6-8H
Renal dose adjustment
SE: hypersensitivity (inc. anaphylaxis), GI upset, drug fever, rash, BMS, AIN, C.diff infection, seizures (accumulation)
Cefprozil
Class: 2nd Generation Cephalosporins
Dosing: 250-500 mg PO Q12H-24H
Renal dose adjustment
SE: hypersensitivity (inc. anaphylaxis), GI upset, drug fever, rash, BMS, AIN, C.diff infection, seizures (accumulation)
Cefuroxime
Ceftin, Zinacef
Class: 2nd Generation Cephalosporins
Dosing: 250-1500 mg Q8-12H
PO, suspension, IV, IM
Renal dose adjustment
SE: hypersensitivity (inc. anaphylaxis), GI upset, drug fever, rash, BMS, AIN, C.diff infection, seizures (accumulation)
Suspension taken with food
3rd Generation Cephalosporins
MOA: inhibit transpeptidation of cell walls by binding PBPs
Time-dependent killing (t/AUC)
Bactericidal
Coverage: Strep, minor Staph, Serratia (HNPEKS), enteric Gm (-) rods
BBW: PCN cross-reactivity
Pregnancy Category B
Cefdinir
Omnicef
Class: 3rd Generation Cephalosporins
Dosing: 300 mg PO Q12H
600 mg PO Q24H
Renal dose adjustment
SE: hypersensitivity (inc. anaphylaxis), GI upset, drug fever, rash, BMS, AIN, C.diff infection, seizures (accumulation)
Cefditoren
Spectracef
Class: 3rd Generation Cephalosporins
Dosing: 200-400 mg PO Q12H
Renal dose adjustment
SE: hypersensitivity (inc. anaphylaxis), GI upset, drug fever, rash, BMS, AIN, C.diff infection, seizures (accumulation)
Tablets take with food
Cefixime
Suprax
Class: 3rd Generation Cephalosporins
Dosing: 400 mg PO div Q12-24H
Tablets, chewable
Renal dose adjustment
SE: hypersensitivity (inc. anaphylaxis), GI upset, drug fever, rash, BMS, AIN, C.diff infection, seizures (accumulation)
Chewable tablets contain phenylalanine
Cefotaxime
Claforan
Class: 3rd Generation Cephalosporins
Dosing: 1-2g IV/IM Q4-12H
Renal dose adjustment
SE: hypersensitivity (inc. anaphylaxis), GI upset, drug fever, rash, BMS, AIN, C.diff infection, seizures (accumulation)
Cefpodoxime
Class: 3rd Generation Cephalosporins
Dosing: 100-400 mg PO Q12H
Renal dose adjustment
SE: hypersensitivity (inc. anaphylaxis), GI upset, drug fever, rash, BMS, AIN, C.diff infection, seizures (accumulation)
Ceftazidime
Fortaz, Tazicef
Class: 3rd Generation Cephalosporins
Coverage: Gm (-) inc. Pseudomonas
No Gm (+) or anaerobes
Dosing: 1-2g IV/IM Q8-12
Renal dose adjustment
SE: hypersensitivity (inc. anaphylaxis), GI upset, drug fever, rash, BMS, AIN, C.diff infection, seizures (accumulation)
Ceftibuten
Cedax
Class: 3rd Generation Cephalosporins
Dosing: 400 mg PO Q24H
Renal dose adjustment
SE: hypersensitivity (inc. anaphylaxis), GI upset, drug fever, rash, BMS, AIN, C.diff infection, seizures (accumulation)
Take suspension on empty stomach
Ceftriaxone
Rocephin
Class: 3rd Generation Cephalosporins
Dosing: 1-2g IV/IM Q12-24H
No renal dose adjustment
SE: hypersensitivity (inc. anaphylaxis), GI upset, drug fever, rash, BMS, AIN, C.diff infection, seizures (accumulation) CNS toxicity (encephalopathy, AMS, seizures)
CI: hyperbilirubinemic neonates, concurrent use of Ca-containing IVs in neonates
4th Generation Cephalosporins
MOA: inhibit transpeptidation of cell walls by binding PBPs
Time-dependent killing (t/AUC)
Bactericidal
Coverage: Strep, minor Staph, HNPEKS, & SPICE A, weak anaerobes
BBW: PCN cross-reactivity
Pregnancy Category B
Cefepime
Maxipime
Class: 4th Generation Cephalosporins
Coverage: Weak anaerobes
No Enterococcus
DOC neutropenic fever
Dosing: 1-2g IV/IM Q12-24H
Renal dose adjustment
SE: hypersensitivity (inc. anaphylaxis), GI upset, drug fever, rash, BMS, AIN, C.diff infection, seizures (accumulation) CNS toxicity (encephalopathy, AMS, seizures)
5th Generation Cephalosporins
MOA: inhibit transpeptidation of cell walls by binding PBPs
Time-dependent killing (t/AUC)
Bactericidal
Coverage: Staph (inc. MRSA), VRSA, Strep, Enterococcus (inc. VRE), HNPEKS
No ESBL or Pseudomonas
BBW: PCN cross-reactivity
Pregnancy Category B
Ceftaroline fosamil
Teflaro
Class: 5th Generation Cephalosporins
Dosing: 600 mg IV Q12H
Renal: 400 mg (CrCl 30-50), 300 mg (15-30), 200 mg (
Ceftolozane/Tazobactam
Zerbaxa
Class: 5th Generation Cephalosporin/Beta-lactamase Inhibitor
Dosing: 1.5g IV Q8H
Renal: 750 mg (CrCl 30-50), 375 mg (15-29)
SE: hypersensitivity (inc. anaphylaxis), GI upset, drug fever, rash, BMS, AIN, C.diff infection, seizures (accumulation)
Indications: complicated intra-abdominal infections & UTIs
Cephalosporin Drug Interactions
Probenecid: reduced PCN renal elimination
Warfarin: increased INR by inhibition of Vit K-dependent clotting factors
Carbapenems
MOA: inhibit transpeptidation of cell walls by binding PBPs
Time-dependent killing (t/AUC)
Bactericidal
Coverage: Gm (+), Gm (-) inc. SPICE A & ESBLs
No atypicals, MRSA, VRE,
Stenotropomonas
BBW: PCN cross-reactivity, CNS adverse effects (seizures, AMS)
Pregnancy Category B/C (Imipenem)
Imipenem/Cilastatin
Primaxin
Class: Carbapenem/DHP-1 Inhibitor
Dosing: 250-1000 mg IV Q6-8H
SE: hypersensitivity (inc. anaphylaxis), rash, GI upset, BMS, seizures (accumulation)
Highest risk of seizures with renal impairment
Meropenem
Merrem
Class: Carbapenems
Dosing: 500-2000 mg IV Q8H
Renal: Q12H (CrCl 26-50), 1/2 dose Q12H (10-25), 1/2 dose Q24H (
Ertapenem
Invanz
Class: Carbapenems
Coverage: no Pseudomonas or Acinetobacter
Dosing: 1g IV/IM Q24H
Renal: 500 mg (CrCl
Doripenem
Doribax
Class: Carbapenems
Dosing: 500 mg IV Q8H
Renal: 250 mg (CrCl 30-50), 250 mg Q12H (11-29)
SE: hypersensitivity (inc. anaphylaxis), GI upset, rash, BMS, seizures (accumulation)
Increased mortality/decreased cure rate in HCAP/VAP- do not use
Carbapenem Drug Interactions
Probenecid: reduced PCN renal elimination
Depakote: decreased [VPA] lessens seizure control
Monobactams
MOA: inhibit transpeptidation of cell walls by binding PBPs
Time-dependent killing (t/AUC)
Bactericidal
Coverage: Gm (-) inc. Pseudomonas
No Gm (+)
Pregnancy Category B
Can be used in PCN allergic patients
Aztreonam
Azactam IV, Cayston
Class: Monobactams
Dosing: 500-2000 mg IV Q6-12H
Renal: 50% normal (CrCl 10-30), 25% (
Fluoroquinolones
MOA: inhibits topoisomerase IV & II (DNA gyrate) & prevents DNA supercoiling, promoting breakage of double-stranded DNA
Coverage: Gm (+), Gm (-), atypicals
Respiratory FQ (G/L/M):
enhanced Strep & atypical
C/L: Pseudomonas
BBW: tendon inflammation/rupture, QT prolongation, peripheral neuropathies, CNS effects, photosensitivity
Pregnancy Category C
Caution with use in children
