metronidazole

Adult Dosing .

Dosage forms:  CAP: 375 mg; TAB: 250 mg, 500 mg; INJ: various

infections, bacterial

[500 mg PO q6-8h x7-14 days]

Alt: 15 mg/kg/dose IV x1, then 7.5 mg/kg/dose IV q6h; Max: 1 g/dose, 4 g/day

amebic liver abscess

[500-750 mg PO q8h x5-10 days]

intestinal amebiasis

[750 mg PO q8h x5-10 days]

PID

[mild-moderate infection]

Dose: 500 mg PO q12h x14 days; Info: give w/ ceftriaxone and doxycycline, cefotaxime and doxycycline, or cefoxitin plus probenecid and doxycycline; 1st-line agent; if cephalosporin allergy and low gonorrhea risk, may give w/ azithromycin, levofloxacin, or moxifloxacin

[severe infection]

Dose: 500 mg PO/IV q12h x14 days; Info: give w/ ceftriaxone plus doxycycline, cefotetan, cefoxitin, ampicillin/sulbactam, or cefotaxime plus metronidazole; 1st-line agent; if cephalosporin allergy and low gonorrhea risk, may give w/ azithromycin, levofloxacin, or moxifloxacin; switch to PO regimen ASAP to complete course

bacterial vaginosis

[500 mg PO q12h x7 days]

Info: may also consider 250 mg PO q8h x7 days in pregnant pts; 1st-line agent

trichomoniasis

[treatment, females]

Dose: 500 mg PO q12h x7 days; Info: give 2 g PO qd x7 days if recurrent infection and no re-exposure

[treatment, males]

Dose: 2 g PO x1; Info: give 500 mg PO q12h x7 days if recurrent infection and no re-exposure

[presumptive tx (off-label)]

Dose: 500 mg PO q12h x7 days; Info: for female sexual assault victims; give w/ ceftriaxone and doxycycline

infection prophylaxis, surgical

[PO route]

Dose: 1000 mg PO at 1pm, 2pm, and 11pm the day before 8am surgery; Info: for colorectal surgery; dosing protocols may vary; give w/ neomycin sulfate; use w/ mechanical bowel prep; follow w/ appropriate preop IV antibiotic prophylaxis

[IV route]

Dose: 500 mg IV x1; Start: w/in 60min preop

giardiasis (off-label)

[250 mg PO q8h x5-7 days]

Alt: 2 g PO q24h x3 days

C. difficile infection (off-label)

[non-severe]

Dose: 500 mg PO q8h x10 days; Info: for 1st episode; not 1st-line agent; consider for use in pts w/ low risk for C. difficile infection recurrence

[fulminant, adjunct]

Dose: 500 mg IV q8h; Info: give w/ vancomycin PO

H. pylori infection (off-label)

[1-2 g/day PO divided bid-qid x14 days]

Info: part of multi-drug regimen; search 'H. pylori Tx' for epocrates H. pylori Tx Regimens decision tool

renal dosing

[no adjustment]

renal impairment: no adjustment

HD: no adjustment, on dialysis days admin. after dialysis; consider supplement if next maint. dose not due right after dialysis; PD: no adjustment; no supplement

hepatic dosing

[adjust dose amount]

severe impairment: decr. usual dose by 50%

Peds Dosing .

Dosage forms:  CAP: 375 mg; TAB: 250 mg, 500 mg; INJ: various

amebiasis

[35-50 mg/kg/day PO divided q8h x7-10 days]

Max: 750 mg/dose; 2250 mg/day

infections, bacterial (off-label)

[neonates <1.2 kg]

Dose: 7.5 mg/kg/dose PO/IV q48h

[neonates <7 days old, >1.2 kg]

Dose: 7.5-15 mg/kg/day PO/IV divided q12-24h

[neonates 7 days old and older, >1.2 kg]

Dose: 15-30 mg/kg/day PO/IV divided q12h

[infants/children]

Dose: 30 mg/kg/day PO/IV divided q6h; Max: 4 g/day

infection prophylaxis, surgical (off-label)

[PO route]

Dose: 15 mg/kg/dose PO at 1pm, 2pm, and 11pm the day before 8am surgery; Max: 1000 mg/dose; Info: for colorectal surgery in pts 1 yo and older; dosing protocols may vary; give w/ neomycin sulfate; use w/ mechanical bowel prep; follow w/ appropriate preop IV antibiotic prophylaxis

[IV route]

Dose: 15 mg/kg/dose IV x1; Start: w/in 60min preop; Max: 500 mg/dose; Info: for pts 1 yo and older

PID (off-label)

[mild-moderate infection, adolescents]

Dose: 500 mg PO q12h x14 days; Info: give w/ ceftriaxone and doxycycline, cefotaxime and doxycycline, or cefoxitin plus probenecid and doxycycline; 1st-line agent; if cephalosporin allergy and low gonorrhea risk, may give w/ azithromycin, levofloxacin, or moxifloxacin

[severe infection, adolescents]

Dose: 500 mg PO/IV q12h x14 days; Info: give w/ ceftriaxone plus doxycycline, cefotetan, cefoxitin, ampicillin/sulbactam, or cefotaxime plus metronidazole; 1st-line agent; if cephalosporin allergy and low gonorrhea risk, may give w/ azithromycin, levofloxacin, or moxifloxacin; switch to PO regimen ASAP to complete course

bacterial vaginosis (off-label)

[preadolescents <45 kg]

Dose: 15-25 mg/kg/day PO divided q8h x7 days; Max: 2 g/day; Info: 1st-line agent

[preadolescents >45 kg and adolescents]

Dose: 500 mg PO q12h x7 days; Info: may also consider 250 mg PO q8h x7 days in pregnant pts; 1st-line agent

trichomoniasis (off-label)

[treatment, preadolescents <45 kg]

Dose: 45 mg/kg/day PO/IV divided q8h x7 days; Max: 2 g/day

[treatment, female preadolescents >45 kg and adolescents]

Dose: 500 mg PO q12h x7 days; Info: give 2 g PO qd x7 days if recurrent infection and no re-exposure

[treatment, male preadolescents >45 kg and adolescents]

Dose: 2 g PO x1; Info: give 500 mg PO q12h x7 days if recurrent infection and no re-exposure

[presumptive tx, adolescents]

Dose: 500 mg PO q12h x7 days; Info: for female sexual assault victims; give w/ ceftriaxone and doxycycline

C. difficile infection (off-label)

[non-severe]

Dose: 30 mg/kg/day PO divided q6h x10 days; Max: 2 g/day; Alt: 30 mg/kg/day IV divided q6h x10 days; Info: for 1st episode or 1st recurrence; 1st-line agent

[severe or fulminant, adjunct]

Dose: 30 mg/kg/day IV divided q6h x10 days; Max: 2 g/day; Info: for 1st episode; give w/ vancomycin PO/PR

H. pylori infection (off-label)

[15-24 kg]

Dose: 250 mg PO bid x10-14 days; Info: part of multi-drug regimen; search 'H. pylori Tx' for epocrates H. pylori Tx Regimens decision tool

[25-34 kg]

Dose: 500 mg PO qam and 250 mg PO qpm x10-14 days; Info: part of multi-drug regimen; search 'H. pylori Tx' for epocrates H. pylori Tx Regimens decision tool

[>35 kg]

Dose: 500 mg PO bid x10-14 days; Info: part of multi-drug regimen; search 'H. pylori Tx' for epocrates H. pylori Tx Regimens decision tool

renal dosing

[see below]

CrCl >10: no adjustment; CrCl <10: not defined, consider adult renal dosing for guidance

HD/PD: not defined, consider adult renal dosing for guidance

hepatic dosing

[adjust dose amount]

severe impairment: decr. usual dose by 50%