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 (l g ampicillin sodium and 0.5 g sulbactam sodium), 3 g (2 g ampicillin sodium and l 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 (l g ampicillin and 0.5 g sulbactam to 2 g ampicillin and l g sulbactam) I.M. or I.V. q 6 hours. Maximum dosage is 4 g sulbactam daily.

Children ages 1 year and older: 75 mg (50 mg ampicillin and 25 mg sulbactam)/kg I.V. q 6 hours

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.

Route	Onset	Peak	Duration
I.V.	Immediate	End of infusion	6-8 hr
I.M.	Rapid	1 hr	6-8 hr

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.