Dosing and uses of Ampi, Omnipen (ampicillin)
Adult dosage forms and strengths
capsules
- 250mg
- 500mg
oral suspension
- 125mg/5mL
- 250mg/5mL
powder for injection
- 125 mg
- 250mg
- 500mg
- 1 g
- 2 g
- 10 g
General Dosing Guidelines
PO: 250-500 mg q6hr
IV/IM: 1-2 g q4-6hr
Endocarditis Prophylaxis
2 g IV/IM (±gentamicin 1.5 mg/kg for GI/GU) within 30 minutes before procedure
Recent AHA Guidelines recommend only for high risk patients
Genitourinary Tract Infections (Excluding Gonorrhea)
500 - 2000 mg IV q6hr
GI Tract Infections
500 mg IV q6hr
Gonorrhea
3.5 g IV administered once simultaneously with 1 g of probenecid
Respiratory Tract Infections
250 mg IV q6hr
Renal Impairment
CrCl <10 mL/min: use q12-16hr
Other Information
Take on empty stomach
Other Indications & Uses
Shigella, Salmonella, E. coli, H. influenzae, Proteus mirabilis, N. gonorrhoeae, enterococci infections, N. meningitidis meningitis, gram-pos. staph, strep, pneumococci
Pediatric dosage forms and strengths
capsules
- 250 mg
- 500 mg
oral suspension
- 125 mg/5mL
- 250 mg/5mL
powder for injection
- 125 mg
- 250 mg
- 500 mg
- 1 g
- 2 g
General Dosing Guidelines
100-400 mg/kg/day IV/IM divided q6hr
50-100 mg/kg/day PO divided q6hr
Severe infection: 200-400 mg/kg/day IV/IM divided q6hr
Neonates (<28 Days Old)
<7 days old
- <2 kg: 50-100 mg/kg/day divided q12hr IV/IM
- >2 kg: 75-150 mg/kg/day divided q8hr IV/IM
>7 days old
- <1.2 kg: 50-100 mg/kg/day divided q12hr IV/IM
- 1.2-2 kg: 75-150 mg/kg/day divided q8hr IV/IM
- >2 kg: 100-200 mg/kg/day divided q6hr IV/IM
Endocarditis Prophylaxis
50 mg/kg (+/- gentamicin 1.5 mg/kg for GI/GU) IV/IM within 30 minutes before procedure
Recent AHA Guidelines recommend only for high risk patients
Genitourinary Tract Infections
<20 kg: 50-100 mg/kg/day IV divided q6hr
>20 kg: 500 mg IV q6hr
GI Tract Infections
<20 kg: 50-100 mg/kg/day IV divided q6hr
>20 kg: 500 mg IV q6hr
Gonorrhea
<20 kg: Safety & efficacy not established
>20 kg: 3.5 g IV administered once simultaneously with 1 g of probenecid
Respiratory Tract Infections
<20 kg: 50 mg/kg/day IV divided q6-8hr
>20 kg: 250 mg IV q6hr
Cholera
50 mg/kg/day PO divided q6hr for 3 days; not to exceed 2 g/day
Other Information
Potential toxic dose <6 years old: 300 mg/kg
Take on empty stomach
Ampi, Omnipen (ampicillin) adverse (side) effects
Frequency not defined
Erythema multiforme
Exfoliative dermatitis
Rash
Urticaria
Fever
Seizure
Black hairy tongue
Diarrhea
Enterocolitis
Glossitis
Nausea
Oral candidiasis
Pseudomembranous colitis
Stomatis
Vomiting
Agranulocytosis
Anemia
Hemolytic anemia
Eosinophilia
Leukopenia
Thrombocytopenia purpura
Anaphylaxis
AST increased
Interstitial nephritis
Laryngeal stridor
Serum sickness like reaction
Warnings
Contraindications
Hypersensitivity
Infectious mononucleosis
Cautions
Allergy to cephalosporins, carbapenems
Adjust dose in renal failure; evaluate rash and differentiate from hypersensitivity reaction
Endocarditis prophylaxis: Use only for high risk patients, per recent AHA Guidelines
Pregnancy and lactation
Pregnancy category: B
Lactation: Excreted in breast milk, use caution
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of Ampi, Omnipen (ampicillin)
Half-Life: 1-1.8 hr
Protein Bound: 15-25%
Peak Plasma Time: Oral 1-2 hr
Absorption: oral 50%
Distribution: bile, blister & tissue fluids, CSF with inflamed meninges
Metabolism: liver
Excretion: urine
Mechanism of action
Broad-spectrum penicillin. Interferes with bacterial cell wall synthesis during active replication, causing bactericidal activity against susceptible organisms. Alternative to amoxicillin when unable to take medication orally.
Administration
IV Compatibilities
Solution: NS (some contrary reports)
Additive: clindamycin, erythromycin, floxacillin, furosemide, metronidazole, verapamiL
Syringe: chloramphenicol, colistimethate, heparin, lidocaine
Y-site (partial list): acyclovir, aztreonam, clarithrmycin, cyclophodsphamide, esmolol, famotidine, heparin, labetalol, linezolid, KCl, MgSO4, meperidine, propofol, vancomycin, vit B/C
IV Incompatibilities
Solution: dextran & dextrose solutions, LR, Ringer's, Na-bicarb, Na-lactate 1/6 M, IV fat emuslions, invert sugar solutions
Additive: amikacin, azrtreonam(?), cefepime(?), chlorpromazine, dopamine, gentamicin, heparin(?), hydralazine, hydrocortisone, prochlorperazine,
Syringe: erythromycin, gentamicin, hydromorphone, kanamycin, lincomycin, metoclopramide, polymyxin B SO4, streptomycin
Y-site: ampho B cholesteryl SO4, Ca gluconate, cisatracurium (at high cisatra conc, may be compatible at low concs), diltiazem, epinephrine, fenoldopam, fluconazole, hydralazine, midazolam, nicardipine, ondansetron, sargramostim, verapamil, vinorelbine
IV Preparation
Reconstitute w/ SWI or BWI
Use 5 mL for 125 mg, 250 mg, or 500 mg vials; 7.4 mL for 1 g vials; or 14.8 mL for 2 g vials
IV Administration
Use initial dilution w/in 1 hr
Give direct IV over 3-5 min for (125-500 mg) and over 10-15 minutes for larger doses (1-2 g)
Don't exceed a rate of 100 mg/min
For intermittent infusion, dilute in 50-100 mL of NS and give over 15-30 min
Give IV intermittently to prevent vein irritation
- Change site q48hr
