Table 8. Adult parenteral antimicrobial dosage guidelinesa
Antibiotic
Table 9. Parenteral to oral conversion suggestions
Usual Dosagesb
Parenteral Drug
ANTIBACTERIAL AGENTS
Penicillins
Amoxicillin
Cloxacillin
2 g q4-6h
Cloxacillin
Cloxacillin, Cephalexin
Penicillin G
1-2 million units q4-6h
Penicillin G
Penicillin V
Piperacillin-Tazobactam
Amoxicillin-Clavulanate
Co-trimoxazole (TMP-SMX) +/- Metronidazole
Ciprofloxacin +/- Metronidazole
3.375 g q6h
Meropenem
500 mg q6h
Cephalosporins
Cefoxitin
1-2 g q6-8h
Cefuroxime
0.75-1.5 g q8h
Ceftriaxone
1-2 g q24h
Ceftazidime
1-2 g q8h
Ciprofloxacin
400 mg q12h
Levofloxacin
500-750 mg q24h
Moxifloxacin
400 mg q24h
500 mg q24h
Aminoglycosides
Gentamicin
80 mg q8h
Tobramycin
80 mg q8h
Co-trimoxazole (TMP-SMX)
Metronidazole
Vancomycin
Cefoxitin
Cefuroxime
Co-trimoxazole (TMP-SMX)
Amoxicillin-Clavulanate
Azithromycin, Clarithromycin
Ciprofloxacin
Levofloxacin
Levofloxacin
Azithromycin
Clindamycin
600 mg q8h
Fluconazole
1 g q12h
Fluconazole
100-400 mg q24h
Micafungin
100 mg q24h
ANTIVIRAL AGENTS
5-10 mg/kg q8h
5 mg/kg q12h
Reviewed by the WRHA Antimicrobial Pharmacotherapy Subcommittee November 2013.
b
Based on normal renal function in a 70 kg patient.
Acyclovir
a
b
> 40
(q6h)
20-40
(q8h)
< 20
(q12h)
> 50
(q8h)
10-50
(q12h)
< 10
(q24h)
> 30
(q6-8h)
10-30
(q12-24h)
< 10
(q24h)
> 50
(q8h)
30-50
(q12h)
10-30
(q24h)
Cefuroxime
> 20
(q8h)
10-20
(q12h)
< 10
(q24h)
> 50
(q8h)
25-50
(q12h)
10-25
(q24h)
Acyclovir
Aminoglycosides
> 30
(q12h)
< 30
(q24h)
> 50
(q24h)
20-50
(50% q24h)
< 20
(25% q24h)
50-70
2.5 mg/kg q12h
> 50
(q24h)
> 50
(q6h)
25-50
2.5 mg/kg q24h
20-49
(500 mg load,
then 50% q24h)
30-49
(q8h)
10-25
1.25 mg/kg q24h
10-19
(500 mg load,
then 50% q48h)
10-29
(q12h)
TMP-SMX
> 25
(q6-8h)
15-25
(50% q6-8h)
Vancomycind
> 70
(q12h)
50-70
(q24h)
Fluconazole
Ganciclovir
(induction doses)
Levofloxacin
(e.g. CAP)
Cloxacillin +/- Metronidazole
Cephalexin +/- Metronidazole
Clindamycin
Meropenem
NO CHANGE NECESSARY
Metronidazole
Fluconazole
Reviewed by the WRHA Antimicrobial Pharmacotherapy Subcommittee November 2013.
Selection of oral therapy should be based on cultures and sensitivities. In absence of useful cultures, oral
therapy may be selected based on potential pathogens, community- versus hospital-acquired infection,
pharmacokinetics, spectrum of activity, and cost of each oral agent. Oral agents listed above represent those
currently on the WRHA Formulary and does not represent all commercially available oral agents.
< 10
(50% q24h)
NO CHANGE NECESSARY
Clindamycin
Azithromycin
Acyclovir
< 10
(50% q24-48h)
Contact the Pharmacist at your facility for dosing assistance
d
Azithromycin
ANTIVIRAL AGENTS
0.5-1 mg/kg q24h
< 10
(20-50%)b
Victoria General Hospital
Antibiogram for 2015
(Based on data from 2014)
Miscellaneous
ANTIFUNGAL AGENTS
500 mg q8h
10-50
(q6-8h)
Ceftazidime
Ciprofloxacin
Ciprofloxacin
10-20 mg/kg/day trimethoprim in divided doses q6-8h
Amphotericin B
Ganciclovir
Amoxicillin-Clavulanate
Cephalexin
Ciprofloxacin, Levofloxacin
Others
ANTIFUNGAL AGENTS
Acyclovir
Ceftriaxone
Ciprofloxacin
> 50
(q4-6h)
NO CHANGE NECESSARY
Macrolides
Others
Clindamycin
Cefazolin
Ceftriaxone
Ceftazidime
< 10
(q12h)
Cephalosporins
Fluoroquinolones
Macrolides
Azithromycin
Piperacillin
(± Tazobactam)
Cephalexin, Cloxacillin
Cephalexin + Metronidazole
Co-trimoxazole (TMP-SMX) + Metronidazole
Amoxicillin-Clavulanate
10-30
(q6-12h)
NO CHANGE NECESSARY
Penicillin
Cefazolin
Cefoxitin
> 30
(q6h)
Cloxacillin
Cephalosporins
1-2 g q8h
Fluoroquinolones
a
Ampicillin
Ampicillin
Piperacillin-Tazobactam
Creatinine Clearance (CrCl) in mL/minc
(suggested dosage adjustment based on normal dose)
Penicillins
1-2 g q6h
Cefazolin
Drug
ANTIBACTERIAL AGENTS
Penicillins
Ampicillin
Table 10. Adult dosing recommendations in renal impairmenta, b
Oral Therapy Optionsa, b
For further information contact:
< 10
1.25 mg/kg 3x/wk
< 10
(q24h)
NO CHANGE NECESSARY
< 15
(2.5-5 mg/kg, generally not recommended)b
10-49
(q24-72h)
< 10
(q5-7days)
Reviewed by the WRHA Antimicrobial Pharmacotherapy Subcommittee November 2013.
b
Suggested dosages – for individualized dosage modifications or more information contact the Pharmacy
Department at your facility.
c
To estimate creatinine clearance (CLCR) (mL/min) use the following calculation normalized for a 72 kilogram person.
CLCR male = (140-age) x 88.4
CLCR female = 0.85 x CLCR male
SCR (μmoles/L)
d
Monitor serum concentrations.
a
Provided by:
Diagnostic Services Manitoba, Clinical Microbiology Discipline
Andrew Walkty, MD, FRCPC
Medical Microbiologist, Health Sciences Centre/Diagnostic Services Manitoba
or
Daryl J. Hoban, PhD, D(ABMM), FCCM
Clinical Microbiologist, Health Sciences Centre/Diagnostic Services Manitoba
or
Philippe Lagacé-Wiens, MD, FRCPC
Medical Microbiologist, St. Boniface Hospital/Diagnostic Services Manitoba
Reviewed by the WRHA Antimicrobial Pharmacotherapy Subcommittee November 2013
62
100
TrimethoprimSulfamethoxazole
100
100
100
80
80
78
86
98
60
100
Methicillin Resistant
Staphylococcus aureus (53)
0
100
96
84
87
97
98
23
72
100
100
Isolates tested and reported are from all sources (surveillance isolates excluded), Jan to Dec, 2014; data
compiled according to the recommendations of the Clinical and Laboratory Standards Institute (CLSI) in their
document M39-A4 (2014).
b
Oxacillin accurately predicts the activity of all semi-synthetic penicillins, including cloxacillin, beta-lactam/
beta‑lactamase inhibitor combinations, cephalosporins, and carbapenems for Staphylococcus aureus.
Table 5. In vitro activity of selected anti-infective agents tested against anaerobic isolates
collected at the Health Sciences Centre, Winnipega
Percent Susceptible
Organism (number tested)
=Not tested, not
routinely reported, or
not recommended
Bacteroides fragilis group (70)
(includes Bacteroides fragilis)
a
81
100
56
49
100
100
Isolates tested and reported are from all sources. Data were extracted from the CANAEROBES study (Zhanel
et al.).
100
97
Antibiotic
ANTIBACTERIAL AGENTS
Penicillins
Amoxicillin
Amoxicillin-Clavulanate
Cloxacillin
Penicillin V
Cephalosporins
Cephalexin
Macrolides
Azithromycin
Clarithromycin
Erythromycin
Fluoroquinolones
Ciprofloxacin
Levofloxacin
Moxifloxacin
Others
Clindamycin
Co-trimoxazole (TMP-SMX)
Doxycycline
Nitrofurantoin
Trimethoprim
Metronidazole
ANTIFUNGAL AGENTS
Fluconazole
Itraconazole
ANTIVIRAL AGENTS
Acyclovir
Valacyclovir
a
b
100
n.d.
Table 7. Adult oral antimicrobial dosage guidelinesa
Linezolid
Tetracycline
Methicillin Susceptible
Staphylococcus aureus (168)
97
100
Data obtained by testing a random sample of C. albicans and C. glabrata isolates from Health Sciences Centre
and St. Boniface Hospital, collected between Jan 2010 and Dec 2012. Susceptibility interpretations are based
on updated CLSI breakpoints (M27-S4). Isolates tested and reported are from blood only.
b
For fluconazole, there is only a susceptible-dose dependent (SDD) breakpoint for C. glabrata. The percentage
of C. glabrata isolates that tested SDD to fluconazole was 100%. Susceptibility of SDD isolates to fluconazole
is dependent on achieving the maximum blood level possible (i.e., should use the maximum dosage regimen).
Consultation with infectious diseases is recommended for further guidance.
n.d. = breakpoints have not been defined for voriconazole versus C. glabrata
Percent Susceptible
=Not tested, not
routinely reported, or
not recommended
Candida albicans (30)
Candida glabrata (30)
a
Table 4. In vitro activity of selected anti-infective agents tested against Methicillin
Susceptible and Methicillin Resistant Staphylococcus aureus isolates
Organism (number tested)
Micafungin
Clindamycin
100
Voriconazole
Clarithromycin
70
Organism (number tested)
Fluconazoleb
Levofloxacin
92
92
Clindamycin
92
98
100
100
92
Erythromycin
Nitrofurantoin
98
Isolates tested and reported are from all sources (surveillance isolates excluded), Jan to Dec, 2014; data
compiled according to the recommendations of the Clinical and Laboratory Standards Institute (CLSI) in their
document M39-A4 (2014).
Oxacillin accurately predicts the activity of all semi-synthetic penicillins, including cloxacillin, beta-lactam/
beta-lactamase inhibitor combinations, cephalosporins, and carbapenems for Staphylococcus aureus and
Coagulase-negative Staphylococci.
c
Susceptibility to high-level gentamicin or high-level streptomycin indicates that these agents can be used
in combination with a cell wall active agent (e.g. ampicillin or vancomycin) for synergy. Gentamicin and
streptomycin should never be used alone as treatment for Enterococcus spp.
d
Erythromycin activity predicts the activity of azithromycin and clarithromycin for staphylococci and streptococci.
e
Rifampin should NOT be used alone as treatment for infection.
f
Nitrofurantoin is indicated for acute cystitis only.
g
n.a. = not applicable – Susceptibility testing of Streptococcus pyogenes is not routinely performed as 100% are
susceptible to penicillin. If treating infection in a penicillin allergic patient, contact the lab for testing of second
line agents.
h
Streptococcus agalactiae isolates were obtained from vaginal/rectal swabs submitted for Group B Streptococcus
detection to the Health Sciences Centre, St. Boniface Hospital, and Westman Laboratory in 2012.
a
73
Data were obtained by testing a random sample of 59 bloodstream isolates and 54 respiratory isolates obtained
from patients at the Health Sciences Centre (HSC) and St. Boniface Hospital (SBH) between January and
December, 2014.
b
For Streptococcus pneumoniae, different susceptibility breakpoints for penicillin and ceftriaxone exist depending
on whether meningitis or a non-meningitis infection is being treated [CLSI, M100-S25]. For penicillin,
when treating a non-meningitis infection different breakpoints exist for oral and intravenous dosing. For
non‑meningitis infections, susceptibility to oral penicillin predicts susceptibility to amoxicillin. Oral agents are not
appropriate for the treatment of bacterial meningitis.
f
Tetracycline
91
100 100
100 100
98
Metronidazole
64
100
100
Imipenem
55
98
100
a
Linezolid
96
Rifampine
83
d
69
88
100
Clindamycin
100
79
88
Cefoxitin
45
84
TrimethoprimSulfamethoxazole
100
100
High-Level
Gentamicinc
High-Level
Streptomycinc
78
Clindamycin
94
Erythromycin
Enterococcus spp. (192)
Staphylococcus aureus (217)
Coagulase-negative
Staphylococci (42)
Streptococcus pyogenes (n.a.)g
(Group A Streptococcus)
Streptococcus agalactiae (162)h
(Group B Streptococcus)
Vancomycin
=Not tested, not routinely
reported, or not
recommended
Vancomycin
28
Percent Susceptible
Organism (number tested):
January through December 2014
Ceftriaxone
93
TrimethoprimSulfamethoxazole
96
97
85
Bloodstream Isolates
Meningitis (59)
Non-Meningitis infection (59)
Respiratory Isolates
Non-Meningitis infection (54)
PiperacillinTazobactam
98
94
98
Penicillin
(intravenous)
99
94
92
25
Vancomycin
Ciprofloxacin
97 98 100 100
100 100 100 100
91 91 100
85
67
70
80
93
85
AmoxicillinClavulanate
Tobramycin
90
64
72
Penicillin
(oral)
Gentamicin
94
84
88
Oxacillinb
Amikacin
96
88
88
Nitrofurantoinc
Meropenem
98 100
100 100
100 100
TrimethoprimSulfamethoxazole
Ceftazidime
Cefuroxime
Cefazolin
AmoxicillinClavulanate
PiperacillinTazobactam
81
88
95
=Not tested, not
routinely reported, or
not recommended
Penicillin
• If anti-infective agent susceptibilities are known, anti-infective therapy should be tailored
based on available data.
88
64
95
77
86
92
Table 6. In vitro activity of selected anti-fungal agents tested against Candida species
collected from hospitals in Winnipega
Percent Susceptible
Infection Type (number tested)
Table 2. In vitro activity of selected anti-infective agents tested against Gram-positive coccia
• Clinical improvement of infectious signs and symptoms (e.g., temperature defervescence,
decreased white blood cell count).
• For rapid step-down, choose agents with high bioavailability (e.g., clindamycin,
co‑trimoxazole (TMP-SMX), fluoroquinolones).
47
63
Isolates tested and reported are from all sources combined, with the exception of Escherichia coli (subdivided
into systemic isolates and urine isolates); isolates were collected from Jan 1 to Dec 31, 2014 with the exception
of Enterobacter cloacae complex (collected from Jan 2013 to Dec 2014); data compiled according to the
recommendations of the Clinical and Laboratory Standards Institute (CLSI) in their document M39-A4 (2014).
b
New breakpoints for cefazolin, ceftriaxone, and ceftazidime were implemented in 2013. This change accounts
for the apparent reduction in cefazolin susceptibility for members of the family Enterobacteriaceae.
c
Nitrofurantoin is indicated for acute cystitis only.
d
H. influenzae data obtained from isolates tested at St. Boniface Hospital and Health Sciences Centre, Jan 1 to
Dec 31, 2014. Seventy-one isolates were tested for Trimethoprim-Sulfamethoxazole.
n.d. = no data – absence of data for certain drug-organism combinations reflects limitations of the testing method
currently used by DSM Clinical Microbiology laboratories.
SUGGESTED CRITERIA FOR IV TO ORAL ANTIBIOTIC CONVERSION IN ADULTS
• Patient can tolerate oral feeding and medications (bowel sounds, no diarrhea/nausea/
vomiting).
82
90
75 97
80 97
n.d.
96 99
n.d. 100
88
Table 3. In vitro activity of selected anti-infective agents tested against Streptococcus
pneumoniaea, b
Percent Susceptible
a
• Consideration should be given to equally efficacious but less expensive anti-infective
agents for empiric therapy or when streamlining of therapy is desired, if the situation
permits.
• Patient is clinically stable (excludes patients in the intensive care unit, patients with febrile
neutropenia, or patients with life threatening infections).
52
56
75
Ceftriaxone
Enterobacter cloacae complex (48)
Escherichia coli (64) systemic
Escherichia coli (436) urine
Haemophilus influenzae (74)d
Klebsiella pneumoniae (94)
Proteus mirabilis (33)
Pseudomonas aeruginosa (67)
Ampicillin
=Not tested, not routinely
reported, or not
recommended
Oxacillin
• Initial broad-spectrum empiric therapy should be focused to the most appropriate
narrow‑spectrum agent(s) based on the laboratory identification of pathogen(s) and known
susceptibility patterns/results, if the situation permits.
Organism (number tested):
January through December 2014
b
• The information presented in the antibiogram is intended only to guide initial empiric
anti‑infective agent therapy at the Victoria General Hospital.
Percent Susceptible
Ampicillin
HOW TO USE THE ANTIBIOGRAM PORTION OF THE GUIDE
(Tables 1-6)
Table 1. In vitro activity of selected anti-infective agents tested against Gram-negative bacillia, b
Penicillin
DISCLAIMERS
This guide is provided as an educational resource for physicians and other healthcare
professionals caring for patients at the Victoria General Hospital. The authors of the guide
have made every effort to ensure that the information contained in it was accurate at the time
of publication. Users of the guide are encouraged to consult other references to confirm
the information presented in it. The authors are not responsible for errors, omissions,
inaccuracies, or the continued completeness of the information contained in the guide. The
information in the guide should not be used or relied upon to replace the skill and professional
judgment required to determine appropriate patient care and treatment. Also, the guide is
not intended to replace or to be used as a substitute for the complete prescribing information
prepared by each pharmaceutical manufacturer for their anti-infective agents. Because of
possible changes in anti-infective indications, changes in dosage information, differences in
patients’ responses to therapy, newly described toxicities, drug-drug interactions, and other
items of importance, reference to complete prescribing information is recommended before
any of the anti-infective agents described in the guide are used.
a
b
Usual Dosages
Cost ($) per dayb
250 – 500 mg tid
250 – 500 mg tid
250 – 500 mg qid
300 mg qid
0.60 – 1.10
2.10 – 3.10
0.80 – 1.50
0.30
250 – 500 mg qid
0.90 – 1.80
250 – 500 mg daily
250 – 500 mg bid
250 – 500 mg qid
3.10 – 6.20
2.20 – 4.50
0.80 – 1.60
250 – 750 mg bid
500 - 750 mg daily
400 mg daily
2.80 – 6.00
3.50 – 7.00
5.00
300 – 450 mg tid
1 DS (double strength) tab bid
100 mg bid
50 – 100 mg qid
100 mg bid
500 mg tid
3.30 – 5.00
0.30
1.30
0.70 –1.50
0.75
0.35
100 – 400 mg daily
200 – 400 mg daily
6.10 – 25.00
8.00 – 16.00
200 – 800 mg 5x/day
500 mg – 1 g tid
5.00 – 16.00
8.00 – 16.00
Reviewed by the WRHA Antimicrobial Pharmacotherapy Subcommittee November 2013.
Approximate cost per inpatient day excluding dispensing costs as of February 2010 based on the Manitoba
Drug Interchangibility Formulary and Manufacturer’s List Prices. Prices have been rounded.