Aztreonam

Aztreonam is a synthetic bactericidal monobactam antibiotic. It inhibits bacterial cell wall synthesis by blocking peptidoglycan crosslinking. The inhibition of bacterial cell wall synthesis occurs due to a high affinity of Aztreonam for penicillin binding protein 3 (PBP3). By binding to PBP3, Aztreonam inhibits the third and last stage of bacterial cell wall synthesis. Cell lysis is then mediated by bacterial cell wall autolytic enzymes such as autolysins. It is possible that Aztreonam interferes with an autolysin inhibitor.

Adults: The recommended dosage for Urinary tract infections , Moderately severe systemic infections and Severe systemic or life-threatening infections is 500 mg or 1 g , 1 g or 2 g, 2 g every 8 or 12, 8 or 12 and 6 or 8 hourly respectively.

Children: The recommended dosage for Mild to moderate infections (Over 1 week) and Moderate to severe infections (2 years or older) is 30 mg/kg and 50 mg/kg every 6 and 6 or 8 hourly respectively. Maximum recommended dose for adult is 8 g per day. Maximum recommended dose for pediatric patient is 120 mg/kg/day.

Pediatric use: Dosage information is not yet available for new born less than one week.

Intramuscular administration: The dose should be given by deep injection into a large muscle mass. Aztreonam is well tolerated and should not be administered with any local anesthetic agent. For each gram of Aztreonam add at least 3 ml water for injection BP and shake well.

Intravenous administration: A bolus injection may be used to initiate therapy. The dose should be slowly injected directly into a vein, or the tubing of a suitable administration set, over a period of 3 to 5 minutes.

For infusion: Each gram of Aztreonam should be initially constituted with at least 3 ml of water for injection BP. The resulting solution should be diluted with an appropriate infusion solution to a final concentration not exceeding 2% w/v (at least 50 ml solution per gram Aztreonam). The Aztreonam infusion should be administered over a 20-60 minute period. A number of intravenous solutions may be used as diluents for the administration of Aztreonam by intravenous infusion.These include sodium chloride injection, dextrose and mixed injections of sodium chloride and dextrose, Ringers and lactated Ringers injection,water for injection etc.

Concomitant administration of probenecid or furosemide and Aztreonam causes clinically insignificant increases in the serum levels of Aztreonam.

This preparation is contraindicated in patients with known hypersensitivity to Aztreonam or any other component in the formulation.

Local reactions such as phlebitis/thrombophlebitis following IV administration and discomfort/swelling at the injection site following IM administration may occur. Systemic reactions like diarrhea, nausea and/or vomiting, and rash may occur. Other side effects include anaphylaxis, angioedema, bronchospasm, pancytopenia, neutropenia, thrombocytopenia, anemia, eosinophilia, leukocytosis, thrombocytosis, abdominal cramps, dermatitis, urticaria, pruritus, hypotension, flushing, seizure, weakness, headache, fever, malaise may occur.

Pregnancy Category B. Aztreonam crosses the placenta and enters the fetal circulation. So it should be used during pregnancy only if the potential benefit justifies the potential risk. Aztreonam is excreted in breast milk in concentrations that are less than 1% of concentrations determined in simultaneously obtained maternal serum. Temporary discontinuation of nursing is recommended.

In patients with impaired hepatic or renal function, appropriate monitoring is recommended during therapy.

Other beta-lactam Antibiotics

Store in a cool & dry place, protected from light & moisture. Keep all medicines out of reach of children.