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Dosage

Antibiotics

Do not use the automated MDRD eGFR produced by the clinical chemistry. It is not appropriate for drug dosing purposes

Acyclovir

Usual dose CrClr Adjusted dose
HSV / Prophylaxis:
5 mg/kg IV q8h for 5 days

HSV / VZV Encephalitis:
10 mg/kg IV q8h for 10 days
upto 14 days in immunocompromised. 		> 50 Usual dose
25 - 50 5 - 10 mg/kg IV q12h
24 - 10 5 - 10 mg/kg IV q24h
0 - 9 2.5 - 5 mg/kg IV q24h
HD 2.5 - 5 mg/kg IV q24h
after dialysis
Non genital HSV:
200 mg PO q4h (5 x daily) for 5 days		 > 10 Usual dose
0 - 10 200 mg PO q12h
Genital HSV / HIV +ve:
400 mg PO q4h (5 x daily) - 12h for 7-10 days		 > 10 Usual dose
0 - 10 200 - 400 mg PO q12h
VZV:
800 mg PO q4h (5 x daily) - 12h for 7 days		 > 25 Usual dose
24 - 10 800 mg PO q8 - 12h
0 - 9 400 - 800mg PO q12h
HD 800 mg PO q12h
after dialysis

Amoxicillin

Usual dose CrClr Adjusted dose
500 mg - 1 gm PO q8h > 30 Usual dose
24 - 10 250 - 875 mg PO q12h
< 10 250 - 875 mg PO q24h
HD 250 - 875 mg PO q24h + 250 - 500 mg
after dialysis

Augmentin

Usual dose CrClr Adjusted dose
500/125 PO q8h > 15 Usual dose
15 - 5 500/125 mg q12h
< 5 250/125 mg q24h
HD 500/125 mg q24h + 250 - 500mg
after dialysis
1.2 gm q8h - q6h IV
 > 15 Usual dose
15 - 5 1.2 gm q12h
< 5 1.2 gm q24h
HD 1.2 gm q24h + 250 - 500mg
after dialysis

Ampicillin

Usual dose CrClr Adjusted dose
250 mg - 1 gm IV q6h

Endocarditis:
2 gm IV q6h 		> 30 Usual dose
30 - 10 Usual dose q6 - 8h
< 10 Usual dose q8h
HD Usual dose q8h + supplemental dose
after dialysis

Aztreonam

Usual dose CrClr Adjusted dose
1 - 2 gms IV q8h > 30 Usual dose
30 - 10 load with 1-2 gm, then 500 mg - 1 gm IV q8h
< 10 load with 1-2 gm, then 250 - 500 mg IV q8h
HD dose for CrCl < 10 + supplemental dose
after dialysis

Cefuroxime

Usual dose CrClr Adjusted dose
750 mg - 1.5 gm IV q6h - q8h > 20 Usual dose
10 - 20 750 mg - 1.5 gm IV q12h
< 10 750 mg - 1.5 gm IV q24h

Cefotaxime

Usual dose CrClr Adjusted dose
1 gm q12h - 2 gm IV q6h > 5 Usual dose
< 5 1 gm loading and then ½ normal dose

Clarithromycin

Usual dose CrClr Adjusted dose
250 - 500 mg PO q12h for 5 days
for severe infections / pneumonia upto 14 days. 		> 30 Usual dose
< 30 ½ normal dose
500 mg IV q12h
into larger proximal vein		 > 30 Usual dose
< 30 ½ normal dose

Clindamycin

Usual dose CrClr Adjusted dose
600 mg IV q8h

150 - 300 mg PO q6h
upto 450 mg PO q6h in severe infections. 		no change no change

Doxycycline

Usual dose CrClr Adjusted dose
200 mg on first day
then 100 mg q24h

upto 200 mg q24h for severe infections 		no change no change

Erythromycin

Usual dose CrClr Adjusted dose
250 - 500 mg PO q6 - 12h OR
15 - 20 mg/kg/day IV divided q6h		 > 10 Usual dose
< 10 1.5 gm max

Ethambutol

Usual dose CrClr Adjusted dose
15 - 25 mg/kg/day > 50 Usual dose
10 - 50 usual dose q24 - 36h
< 10 usual dose q48h
HD usual dose after dialysis

Fluconazole

Usual dose CrClr Adjusted dose
Loading Dose: 100 - 800 mg PO/IV q24h
Maintenance Dose: 50 - 800 mg PO/IV q24h		 > 50 Usual dose
< 50 (no HD) 50% normal dose q24h
HD load with 100 - 400 mg, then usual dose after dialysis q48h

Ganciclovir IV

Usual dose CrClr Adjusted dose
Induction: 5 mg/kg IV q12h x 14 - 21 days > 70 5 mg/kg q12h
50 - 69 2.5 mg/kg q12h
25 - 49 2.5 mg/kg q24h
< 25 1.25 mg/kg q24h
HD 1.25 mg/kg 3x/week with doses given after dialysis
Maintenance: 5 mg/kg IV q24h > 70 5 mg/kg q24h
50 - 69 2.5 mg/kg q24h
25 - 49 1.25 mg/kg q24h
<25 0.625 mg/kg q24h
HD 0.625 mg/kg 3x/week with doses given after dialysis

Imipenem IV

Usual dose CrClr Adjusted dose
500 mg IV q6h (2 g/day)
Note that meningitis dose is
higher (up to 1g q 6h, depending
on renal function- consult ID)		 ≥ 71 ≥ 70 kg: 500 mg q6h
60 - 69 kg: 500 mg q8h
50 - 59 kg: 250 mg q6h
40 - 49 kg: 250 mg q6h
30 - 39 kg: 250 mg q8h
41 - 70 ≥ 70 kg: 500 mg q8h
60 - 69 kg: 250 mg q6h
50 - 59 kg: 250 mg q6h
40 - 49 kg: 250 mg q8h
21 - 40 > 70 kg: 250 mg q6h
**In patients undergoing hemodialysis or with a Clcr of 6-20 ml/min, the 500mg IV q 12 hour dose should be reserved for treatment of severe infections. Patients with Clcr < 5 ml/min should not receive imipenem/cilastatin unless dialysis is going to be instituted within 48 hours. These patients may be at an increased risk of seizures.

Isoniazid

Usual dose CrClr Adjusted dose
300 mg PO daily >no change no change

Itraconazole

Usual dose CrClr Adjusted dose
100 - 200 mg PO (capsule /solution) q12h OR

200 mg IV q12h x 4 doses, then 200 mg IV q24h

***IV use NOT TO EXCEED 14 days***		 PO: no change PO: no change
IV: > 30 Usual dose
IV: ≤ 30 not recommended due to injectable excipient