Among the penicillin derivatives listed below, which one is unsuitable for oral administration______________?
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Answer: B. Carbenicillin
Explanation
Carbenicillin is unstable in acidic gastric environments and absorbs poorly from the gut. Oral administration fails to achieve therapeutic blood levels due to acid degradation. Intravenous or intramuscular routes are mandatory to ensure adequate systemic drug delivery. Acid lability prevents certain antibiotics from surviving harsh gastric juice conditions. Parenteral formulations bypass the gastrointestinal tract to deliver drugs directly into tissues. Penicillin derivatives vary widely in their chemical stability and pharmacokinetic properties.
Hospitalized patients with severe systemic infections receive parenteral antipseudomonal penicillins. Choosing the correct route of administration ensures successful treatment of invasive pathogens. Carbenicillin historically expanded treatment options for resistant gram-negative bacterial infections. Amoxicillin features excellent acid stability and reliable oral absorption characteristics. Cloxacillin resists gastric acid degradation and is administered effectively via oral routes. Phenoxymethyl penicillin is specifically formulated to withstand gastric acid for oral use.
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