General MedicationsINTRAMUSCULAR / INTRAVENOUSHigh Alert

AZACTAM

AZTREONAM

Standard Dose

DOSAGE AND ADMINISTRATION Dosage in Adult Patients AZACTAM may be administered intravenously or by intramuscular injection. Dosage and route of administration should be determined by susceptibility of the causative organisms, severity and site of infection, and the condition of the patient. Table 2: AZACTAM Dosage Guidelines for Adults* * Maximum recommended dose is 8 g per day. Type of Infection Dose Frequency (hours) Urinary tract infections 500 mg or 1 g 8 or 12 Moderately severe systemic infections 1 g or 2 g 8 or 12 Severe systemic or life-threatening infections 2 g 6 or 8 Because of the serious nature of infections due to Pseudomonas aeruginosa , dosage of 2 g every six or eight hours is recommended, at least upon initiation of therapy, in systemic infections caused by this organism. The intravenous route is recommended for patients requiring single doses greater than 1 g or those with bacterial septicemia, localized parenchymal abscess (eg, intra-abdominal abscess), peritonitis, or other severe systemic or life-threatening infections. The duration of therapy depends on the severity of infection. Generally, AZACTAM should be continued for at least 48 hours after the patient becomes asymptomatic or evidence of bacterial eradication has been obtained. Persistent infections may require treatment for several weeks. Doses smaller than those indicated should not be used. Renal Impairment in Adult Patients Prolonged serum levels of aztreonam may occur in patients with transient or persistent renal insufficiency. Therefore, the dosage of AZACTAM should be halved in patients with estimated creatinine clearances between 10 and 30 mL/min/1.73 m 2 after an initial loading dose of 1g or 2 g. When only the serum creatinine concentration is available, the following formula (based on sex, weight, and age of the patient) may be used to approximate the creatinine clearance (ClCr). The serum creatinine should represent a steady state of renal function. In patients with severe renal failure (creatinine clearance less than 10 mL/min/1.73 m 2 ), such as those supported by hemodialysis, the usual dose of 500 mg, 1 g, or 2 g should be given initially. The maintenance dose should be one-fourth of the usual initial dose given at the usual fixed interval of 6, 8, or 12 hours. For serious or life-threatening infections, in addition to the maintenance doses, one-eighth of the initial dose should be given after each hemodialysis session. clcr-equation Dosage in the Elderly Renal status is a major determinant of dosage in the elderly; these patients in particular may have diminished renal function. Serum creatinine may not be an accurate determinant of renal status. Therefore, as with all antibiotics eliminated by the kidneys, estimates of creatinine clearance should be obtained and appropriate dosage modifications made if necessary. Dosage in Pediatric Patients AZACTAM should be administered intravenously to pediatric patients with normal renal function. There are insufficient data regarding intramuscular administration to pediatric patients or dosing in pediatric patients with renal impairment. (See PRECAUTIONS: Pediatric Use .) Table 3: AZACTAM Dosage Guidelines for Pediatric Patients* * Maximum recommended dose is 120 mg/kg/day. Type of Infection Dose Frequency (hours) Mild to moderate infections 30 mg/kg 8 Moderate to severe infections 30 mg/kg 6 or 8

Max Dose

See official label

Primary Use

INDICATIONS AND USAGE To reduce the development of drug-resistant bacteria and maintain the effectiveness of AZACTAM (aztreonam for injection, USP) and other antibacterial drugs, AZACTAM should be used only to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria.

Summary

When culture and susceptibility information are available, they should be considered in selecting or modifying antibacterial therapy.

Structured Monograph

Clinical summary

Indications and usage INDICATIONS AND USAGE To reduce the development of drug-resistant bacteria and maintain the effectiveness of AZACTAM (aztreonam for injection, USP) and other antibacterial drugs, AZACTAM should be used only to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria. When culture and susceptibility information are available, they should be considered in selecting or modifying antibacterial therapy. In the absence of such data, local epidemiology and susceptibility patterns may contribute to the empiric selection of therapy. AZACTAM is indicated for the treatment of the following infections caused by susceptible Gram-negative microorganisms: Urinary Tract Infections (complicated and uncomplicated), including pyelonephritis and cystitis (initial and recurrent) caused by Escherichia coli , Klebsiella pneumoniae , Proteus mirabilis , Pseudomonas aeruginosa , Enterobacter cloacae , Klebsiella oxytoca *, Citrobacter species*, and Serratia marcescens *. Lower Respiratory Tract Infections , including pneumonia and bronchitis caused by Escherichia coli , Klebsiella pneumoniae , Pseudomonas aeruginosa , Haemophilus influenzae , Proteus mirabilis , Enterobacter species, and Serratia marcescens *. Septicemia caused by Escherichia coli , Klebsiella pneumoniae , Pseudomonas aeruginosa , Proteus mirabilis *, Serratia marcescens *, and Enterobacter species. Skin and Skin-Structure Infections , including those associated with postoperative wounds, ulcers, and burns, caused by Escherichia coli , Proteus mirabilis , Serratia marcescens , Enterobacter species, Pseudomonas aeruginosa , Klebsiella pneumoniae , and Citrobacter species*. Intra-abdominal Infections , including peritonitis caused by Escherichia coli , Klebsiella species including K. pneumoniae , Enterobacter species including E. cloacae *, Pseudomonas aeruginosa , Citrobacter species* including C. freundii *, and Serratia species* including S. marcescens *. Gynecologic Infections , including endometritis and pelvic cellulitis caused by Escherichia coli , Klebsiella pneumoniae *, Enterobacter species* including E. cloacae *, and Proteus mirabilis *. AZACTAM is indicated for adjunctive therapy to surgery in the management of infections caused by susceptible organisms, including abscesses, infections complicating hollow viscus perforations, cutaneous infections, and infections of serous surfaces. AZACTAM is effective against most of the commonly encountered Gram-negative aerobic pathogens seen in general surgery. ------------------------------- * Efficacy for this organism in this organ system was studied in fewer than 10 infections. Concurrent Therapy Concurrent initial therapy with other antimicrobial agents and AZACTAM is recommended before the causative organism(s) is known in seriously ill patients who are also at risk of having an infection due to Gram-positive aerobic pathogens. If anaerobic organisms are also suspected as etiologic agents, therapy should be initiated using an anti-anaerobic agent concurrently with AZACTAM (see DOSAGE AND ADMINISTRATION ). Certain antibiotics (eg, cefoxitin, imipenem) may induce high levels of beta-lactamase in vitro in some Gram-negative aerobes such as Enterobacter and Pseudomonas species, resulting in antagonism to many beta-lactam antibiotics including aztreonam. These in vitro findings suggest that such beta-lactamase-inducing antibiotics not be used concurrently with aztreonam. Following identification and susceptibility testing of the causative organism(s), appropriate antibiotic therapy should be continued. Dosage and administration DOSAGE AND ADMINISTRATION Dosage in Adult Patients AZACTAM may be administered intravenously or by intramuscular injection. Dosage and route of administration should be determined by susceptibility of the causative organisms, severity and site of infection, and the condition of the patient. Table 2: AZACTAM Dosage Guidelines for Adults* * Maximum recommended dose is 8 g per day. Type of Infection Dose Frequency (hours) Urinary tract infections 500 mg or 1 g 8 or 12 Moderately severe systemic infections 1 g or 2 g 8 or 12 Severe systemic or life-threatening infections 2 g 6 or 8 Because of the serious nature of infections due to Pseudomonas aeruginosa , dosage of 2 g every six or eight hours is recommended, at least upon initiation of therapy, in systemic infections caused by this organism. The intravenous route is recommended for patients requiring single doses greater than 1 g or those with bacterial septicemia, localized parenchymal abscess (eg, intra-abdominal abscess), peritonitis, or other severe systemic or life-threatening infections. The duration of therapy depends on the severity of infection. Generally, AZACTAM should be continued for at least 48 hours after the patient becomes asymptomatic or evidence of bacterial eradication has been obtained. Persistent infections may require treatment for several weeks. Doses s

Monitoring

• WARNINGS Both animal and human data suggest that AZACTAM (aztreonam for injection, USP) is rarely cross-reactive with other beta-lactam antibiotics and weakly immunogenic.
• Treatment with aztreonam can result in hypersensitivity reactions in patients with or without prior exposure.
• (See CONTRAINDICATIONS .) Careful inquiry should be made to determine whether the patient has any history of hypersensitivity reactions to any allergens.
• While cross-reactivity of aztreonam with other beta-lactam antibiotics is rare, this drug should be administered with caution to any patient with a history of hypersensitivity to beta-lactams (eg, penicillins, cephalosporins, and/or carbapenems).

Interaction Notes

• Review official label interaction section.