ampicillin sodium and sulbactam sodium

ampicillin sodium and sulbactam sodium

Unasyn

Pharmacologic class: Aminopenicillin/beta-lactamase inhibitor

Therapeutic class: Anti-infective

Pregnancy risk category B

Action

Destroys bacteria by inhibiting bacterial cell-wall synthesis during microbial multiplication. Addition of sulbactam enhances drug's resistance to beta-lactamase, an enzyme that can inactivate ampicillin.

Availability

Injection: Vials; piggyback vials containing 1.5 g (1 g ampicillin sodium and 0.5 g sulbactam sodium), 3 g (2 g ampicillin sodium and 1 g sulbactam sodium), and 15 g (10 g ampicillin sodium and 5 g sulbactam sodium)

Indications and dosages

Intra-abdominal, gynecologic, and skin-structure infections caused by susceptible beta-lactamase-producing strains

Adults and children weighing 40 kg (88 lb) or more: 1.5 to 3 g (1 g ampicillin and 0.5 g sulbactam to 2 g ampicillin and 1 g sulbactam) I.M. or I.V. q 6 hours. Maximum dosage is 4 g sulbactam daily.

Children ages 1 year and older: 300 mg/kg/day (200 mg ampicillin/100 mg sulbactam) by I.V. infusion q 6 hours in equally divided doses

Dosage adjustment

• Renal impairment

Contraindications

• Hypersensitivity to penicillins, cephalosporins, imipenem, or other beta-lactamase inhibitors

Precautions

Use cautiously in:
• severe renal insufficiency, infectious mononucleosis
• pregnant or breastfeeding patients.

Administration

• Ask patient about history of penicillin allergy before giving.
• Let vial stand several minutes until foam has evaporated before administering drug.
• Don't mix I.V. form with other I.V. drugs.
• Give direct I.V. dose over 10 to 15 minutes.
• Give intermittent infusion in 50 to 100 ml of compatible solution over 15 to 30 minutes.
• Change I.V. site every 48 hours.
• Don't give I.M. to children.

Adverse reactions

CNS: lethargy, hallucinations, anxiety, confusion, agitation, depression, fatigue, dizziness, seizures

CV: vein irritation, thrombophlebitis, heart failure

EENT: blurred vision, itchy eyes

GI: nausea, vomiting, diarrhea, abdominal pain, enterocolitis, gastritis, stomatitis, glossitis, black "hairy" tongue, furry tongue, oral and rectal candidiasis, pseudomembranous colitis

GU: hematuria, hyaline casts in urine, vaginitis, nephropathy, interstitial nephritis

Hematologic: anemia, eosinophilia, agranulocytosis, hemolytic anemia, leukopenia, thrombocytopenic purpura, thrombocytopenia, neutropenia

Hepatic: nonspecific hepatitis

Musculoskeletal: arthritis exacerbation

Respiratory: wheezing, dyspnea, hypoxia, apnea

Skin: rash, urticaria, diaphoresis

Other: pain at injection site, fever, hyperthermia, superinfections, hypersensitivity reactions, anaphylaxis, serum sickness

Interactions

Drug-drug.Allopurinol: increased risk of rash

Chloramphenicol: synergistic or antagonistic effects

Hormonal contraceptives: decreased contraceptive efficacy, increased risk of breakthrough bleeding

Probenecid: decreased renal excretion and increased blood level of ampicillin

Tetracyclines: reduced bactericidal effect

Drug-diagnostic tests.Alanine aminotransferase, alkaline phosphatase, aspartate aminotransferase, bilirubin, blood urea nitrogen, creatine kinase, creatinine, gamma-glutamyltransferase, eosinophils, lactate dehydrogenase: increased levels

Estradiol, estriol-glucuronide, granulocytes, hemoglobin, lymphocytes, neutrophils, platelets, white blood cells: decreased levels

Coombs' test: false-positive result

Urinalysis: red blood cells, hyaline casts

Patient monitoring

• Monitor for signs and symptoms of hypersensitivity reaction.
• Check for signs and symptoms of infection at injection site.

Monitor for seizures when giving high doses.
• Watch for bleeding tendency and hemorrhage.
• Check patient's temperature and watch for other signs and symptoms of superinfection, especially oral or rectal candidiasis.
• Monitor CBC and liver function test results.

Patient teaching

Instruct patient to immediately report signs and symptoms of hypersensitivity reaction, such as rash, fever, or chills.
• Tell patient to report signs and symptoms of infection or other problems at injection site.
• Advise patient to minimize GI upset by eating small, frequent servings of food and drinking plenty of fluids.
• Inform patient that drug lowers resistance to certain infections. Instruct him to report new signs or symptoms of infection, especially in mouth or rectum.

Tell patient to promptly report unusual bleeding or bruising.
• Inform patient taking hormonal contraceptives that drug may reduce contraceptive efficacy. Advise her to use alternative birth control method.
• Instruct patient to avoid activities that can cause injury. Advise him to use soft toothbrush and electric razor to avoid gum and skin injury.
• Inform patient that he may need to undergo regular blood testing during therapy.
• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs and tests mentioned above.