Monobactam

Monobactams are β-lactam compounds wherein the β-lactam ring is alone and not fused to another ring, in contrast to most other β-lactams. They are effective only against aerobic Gram-negative bacteria (e.g., Neisseria, Pseudomonas).

Currently the only commercially available monobactam antibiotic is aztreonam.

Other examples of monobactams are tigemonam,nocardicin A, and tabtoxin.

Adverse effects to monobactams can include skin rash and occasional abnormal liver functions.

They have no cross-hypersensitivity reactions with penicillin but like penicillins can trigger seizures in patients with history of seizures.

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