TABLE M-II
ANTIMICROBIAL PHARMACOLOGY
Body Fluid Concentrations
NOTES:
  1. The values listed below are the expected concentrations achieved after administration of the listed dose in persons with normal renal and hepatic function. Specific levels in a given individual may differ considerably depending upon the various factors influencing antibiotic pharmacokinetics. This table is not intended for use as a dosing guide.
  2. Generally, for intravenously administered antimicrobials, peak serum levels occur 30 minutes after infusion is completed; for intramuscularly administered antimicrobials, peak serum levels occur 1 hour after injection; for orally administered antimicrobials, peak serum levels occur 2 hours after ingestion.
DOSE CODE: A = Adult C = Child N = Newborn
ANTIBIOTIC / DOSE STUDIED / PEAK LEVELS (MCG/ML) / HALF LIFE HOURS / CSF PERCENT CONCENTRATIONS
SERUM / URINE
Amikacin / A 7.5 mg/kg IV
C 7.5 mg/kg IV
N 7.5 mg/kg IV / 20-30
20-25
15-20 / 500-1000
500-1000
500-1000 / 2
1.5
5-7 / Variable, inadequate in adults
Amoxicillin / A 250 mg PO
C 15 mg/kg PO / 3.5-5.0
2.5-8.5 / >200 / 0.7-1.4 / Inadequate
Ampicillin / A 1.0 g IV
A 0.5 g PO
A 2.0 g IM
C 25 mg/kg PO
N 50 mg/kg IM / 40
3-6
4-7
4.1-5.0
100 / 500-1000
250-500
500-1000 / 0.5-1.0 / 10% with inflamed meninges
Cefazolin / A 1.0 g IV
C 17 mg/kg IM
C 17 mg/kg IV
N 20 mg/kg IM / 90-120
45
60
30-35 / >2000 / 1.5 / inadequate
Cefepime / A 1.0 g IV
A 1.0 g IM / 82
30 / 926 / 2 / 15% with inflamed meninges
Cefixime / A 200 mg PO (tab) / 1-4 / >200 / 2.4-4 / inadequate
Cefotetan / A 1 gm IV / 142-180 / 2000 / 2.8-4.6 / inadequate
Ceftazidime / A 1 gm IV
N 50 mg/kg IV / 69
68 / 1000 / 1.4-2.0 / 20% with inflamed meninges
Ceftriaxone / A 1 gm IV
A 1 gm IM
C 50 mg/kg IV
N 50 mg/kg / 123-150
83
69-99
108-141 / 1000 / 5.4-10.9 (A)
4-7.7 (C)
9-16 (N) / 10% with inflamed meninges
adequate for susceptible organisms
Cefuroxime / A 750 mg IV
N 25 mg IU / 51.1
45 / 1000 / 1.2-1.6 / <10%
Cephalexin
(Cephradine as well) / A 0.5 g PO / 15-20 / 500-1000 / 0.5-1.2 / inadequate
Chloramphenicol / A 1 gm PO
A 1 gm IV
C 25 mg/kg IV
N 25 mg/kg IM / 11
4.9-12
28
20 / not adequate / 1.5-4.1 / 45-89% inflamed meninges
Ciprofloxacin / A 500 mg PO
Not to be used in children / 1.5-3.0 / >200 / 3-5 / inadequate (6-10%) for meningitis
Clarithromycin / A 250 mg PO / 1.0 / LOW / 4 / inadequate
Clindamycin / A 150 mg PO
A 600 mg IV
C 5-7 mg/kg IV / 2-4
10
8-10 / not adequate / 2-4 / inflamed: 40
(not used for meningitis)
Dicloxacillin / A 500 mg PO
C 100 mg/kg PO / 10-18
6.5-20 / 300-700 / 0.6-0.8 / inadequate
Daptomycin / A 4-6 mg/kg IV / 60-100 / high / 8.1 / inadequate (~5%)
Ertapenem / A 1 gm IV / 155 / >200 / 4 / (~5%)
Erythromycin
Stereate
Lactobionate / A 250 mg PO
A 1000 mg IV / 2.0
10.0 / not adequate / 1.5-2.0 / inadequate
(2-13)
Gentamicin / A 1.5 mg/kg IV
C (1.5-2.5 yrs)
N 2.5 mg/kg IM / 5-7
4-6
3.5-4.5 / 100-500 / 2
2
3-5 / 10-30
(not generally adequate for treatment of meningitis)
Imipenem / A 500 mg IV
C 2.5 mg/kg IV / 21-58
33.5 / >500 / 1.3
1-1.3 / adequate for susceptible organisms (1-10)
Levofloxacin / A 500 mg PO
A 500 mg IV
Not to be used in children / 5.7 / 435 / 6-8 / 15%
adequate for susceptible organisms
Linezolid / A 600 mg IV/PO
C 10 mg/kg
N 10 mg/kg / 12-14
15.1-16.7
11-13 / - / 4-6 / 70
Meropenem / A 1g IV
C 10 mg/kg IV
C 20 mg/kg IV / 49
28.7
60.2 / >10 / 1 / inflamed meninges:15%
Metronidazole / A 7.5 mg/kg IV
A 250 mg PO / 26
4.6-6.5 / >200 / 6-8 / adequate (43)
Nafcillin / A 1 g IM
A 500 mg/kg IV
C 150 mg/kg IV
N 10 mg/kg IM / 7.6
40
48
22 / >200 / 0.5-1.5 / 20 inflamed meninges
Nitrofurantoin / A 100 mg PO / not adequate / 100-200 / 0.5 / not adequate
Ofloxacin / A 400 mg PO
Not to be used in children / 5
2.9-5.6 / >200 / 4-8 / not routinely recommended for meningitis
Penicillin / A 1 million U IV
N 25,000 U/kg IM / 10-20
12.5-36 / 200-4000 / 0.4-0.9 / ≤5 adequate for susceptible organisms
Pen-G
Benzathine / A 1.2 million U IM
N 50,000 u/kg IM / 0.15 u/ml
1.2 / not adequate / prolonged
Pen-G
Procaine / A 1.2 million U IM
N 50,000 U/kg IM / 2
7.4-8.8 / not adequate
200-400
200-400 / prolonged / may be used for neuro syphilis, but not for meningitis
Penicillin V / A 250 mg PO / 2-3 / 200-400 / 0.5 / not adequate
Piperacillin / A 4 gm IV / 150-300 / 2000 / 0.6-1.3 / 30
Rifampin / A 600 mg PO
C 10 mg/kg PO / 7
3.5-15 / 10-70 / 3 / 50
Tetracycline / A 250 mg PO / 1.5-3.0 / 200-300 / 6-12 / 10 (not used for meningitis)
Tobramycin (See Gentamicin)
Trimethoprim
Sulfamethoxazole / A 160 mg PO
800 mg PO / 1-2
40-60 / 50-100
100-500 / 10-12 / 40
Trimethoprim
Sulfamethoxazole / A 160 mg IV
800 mg IV / 9
105 / 500-1000
500-1000 / 7-12
Vancomycin / A 1 gm IV / 25 / 400-800 / 4-6 / 10-30 (can be unpredictable)
Amphotericin / A 0.75 mg/kg IV / 1.5-2.0 / low / 24-48 15 days / (40) inadequate, except for treatment of cryptococcal meningitis
5-Fluorocytosine / A 2.0 g PO
N 25 mg/kg PO / 40-60
40 / 1000 / 3-4 / 50-100
Fluconazole / A 400 mg PO
C 2 mg/kg PO
Premature neonatal / 6-8
2.9
- / 60-80
-
- / 20-50
15-25
47-74 / 80
-
-
Itraconazole / A 100 mg PO with food
A 100 mg PO fasting
C Not to be used in children / 132
38
- / -
-
- / 21
21
- / inadequate
-
-
Voriconazole / A 200 mg PO / 2.08 / - / Variable / 90

References:

AmericanHospital Formulary System of Drug Information 1997, 2001: American Society of Health System Pharmacists, Bethesda, MD.

Drug Facts & Comparisons: loose-leaf drug information service; J.B Lippincott & Co., St. Louis, MO.