Ampicillin/Sulbactam
General
- Type: Amino-Penicillin with a bacterial beta-lactamase inhibitor
- Dosage Forms: powder for solution
- Dosage Strengths: 1.5g, 3g, 15g
- Routes of Administration: IM, IV
- Common Trade Names: Unasyn
Adult Dosing
General
- 1.5-3g IV/IM q6 hours
- Max: 12g/day
Pediatric Dosing (<40kg)
Unasyn (ampicillin/sulbactam) is formulated at a 2:1 ratio (3g vial = 2g ampicillin + 1g sulbactam)
General
- Mild-moderate[1]
- 100-200mg ampicillin/kg/day IM/IV divided q6 hours
- First Dose: 25-50mg ampicillin/kg IM/IV x 1 (37.5-75mg Unasyn/kg IM/IV x 1)
- Max: 1000mg ampicillin (1500mg Unasyn) per DOSE
- Severe[2]
- 200mg ampicillin/kg/day IM/IV divided q6 hours
- First Dose: 50mg ampicillin/kg IM/IV x 1 (75mg Unasyn/kg IM/IV x 1)
- Max: 2000mg ampicillin (3000mg Unasyn) per DOSE
Indications by Disease
| Disease | Dose | Context |
|---|---|---|
| Dental abscess | 3g IV q6 hours x 7 days | Inpatient |
| Diabetic foot infection | 3g IV q6hrs | Inpatient DFI |
| Endocarditis | 12g/day IV in 4 doses | Native Valve Endocarditis |
| Infectious tenosynovitis | 3g (50mg/kg) IV four times daily | Animal Bites |
| Ludwig's angina | 3g (50mg/kg) IV q6 hrs | Immunocompetent |
| Mammalian bites | 3g IV (50mg/kg) q6hrs | Severe mammalian bite infection |
| Mastoiditis | 3g (50mg/kg) IV q6 hours | Empiric |
| Orbital cellulitis | 3 g IV q6hr | Inpatient |
| Pelvic inflammatory disease | 3g IV q6hr | Inpatient alternative; combined with Doxycycline |
| Peritonsillar abscess | 3 gm (75mg/kg) IV four times daily | Inpatient |
| Pneumonia (main) | 1.5–3g q6h | Inpatient, CAP Non-ICU |
| Postpartum endometritis | 3g IV q6hrs | <48hrs postpartum; combined with Doxycycline |
| Pyelonephritis | 3g IM/IV q6 hours x 14 days | UTI, Pyelonephritis |
Pediatric Dosing
Indications by Disease
| Disease | Dose | Context |
|---|---|---|
| Dental abscess | 50mg/kg IV q6hrs (max 3g/dose) | Pediatric Inpatient |
| Infectious tenosynovitis | 50 mg/kg IV four times daily | Pediatrics |
| Ludwig's angina | 50mg/kg IV q6hrs (max 3g/dose) | Pediatric Immunocompetent |
| Mammalian bites | 50mg/kg IV q6hrs (max 3g/dose) | Pediatric Severe |
| Mastoiditis | 50mg/kg IV q6hrs (max 3g/dose) | Pediatric Empiric |
| Orbital cellulitis | 50mg/kg IV q6hrs (max 3g/dose) | Pediatric Inpatient |
| Peritonsillar abscess | 50mg/kg IV q6hrs (max 3g/dose) | Pediatric Inpatient |
| Skin and soft tissue infections | 200mg ampicillin/kg/day IM/IV divided q6 hours | SSTI |
Special Populations
- Pregnancy: B
- Lactation: Use caution
- Renal Dosing
- Adult
- Pediatric
- Hepatic Dosing
- Adult
- Pediatric
Contraindications
- Allergy to class/drug
Adverse Reactions
Serious
- Anaphylaxis
Common
- Headache
- Itching
- Nausea
- Vomiting
Pharmacology
- Half-life: One hour
- Metabolism:
- Excretion: Renal (75% excreted in active form), Bile (very small amount)[3]
- Mechanism of Action: Bactericidal (Binds to penicillin-binding proteins to block cell wall synthesis), coupled with β-lacatamase inhibitor
Antibiotic Sensitivities[4]
Key
- S susceptible/sensitive (usually)
- I intermediate (variably susceptible/resistant)
- R resistant (or not effective clinically)
- S+ synergistic with cell wall antibiotics
- U sensitive for UTI only (non systemic infection)
- X1 no data
- X2 active in vitro, but not used clinically
- X3 active in vitro, but not clinically effective for Group A strep pharyngitis or infections due to E. faecalis
- X4 active in vitro, but not clinically effective for strep pneumonia
See Also
References
- ↑ Red Book, 2012
- ↑ Red Book, 2012
- ↑ Campoli-Richards DM, Brogden RN. (1987). ". Sulbactam/ampicillin: a review of its antibacterial activity, pharmacokinetic properties, and therapeutic use". Drugs. 33 (6): 577–609. doi:10.2165/00003495-198733060-00003. PMID 3038500
- ↑ Sanford Guide to Antimicrobial Therapy 2014
