Which drug is effective against both pseudomonas and proteus: September 2005

Ans. C: Carbenicillin Carbenicillin is a bactericidal and bacteriolytic antibiotic belonging to the carboxypenicillin subgroup of the penicillins. It has Gram-negative coverage which includes Pseudomonas aeruginosa but limited Gram-positive coverage. The catboxypenicillins are susceptible to degradation by beta-lactamase enzymes, although they are more resistant than ampicillin to degradation. Carbenicillin is also more stable at lower pH than ampicillin. The antibiotic is very soluble in water and is acid-labile. Aqueous solutions are sho-lived. It is a semi-synthetic analogue of the naturally occurring benzyl-penicillin.