d. Broad Spectrum Antipseudomonal Penicillins.
(1) These drugs are widely distributed in most body fluids as with all
penicillins. Carbenicillin is distributed into the non-inflamed CSF (cerebrospinal fluid),
which is not typical of most antibiotics.
(2) The spectrum of activity of these drugs has been increased to combat
Pseudomonas aeruginosa and some strains of Proteus that are resistant to ampicillin.
(3) Patients taking large doses of these antibiotics must have their serum
sodium levels closely monitored as these drugs contain excessive amounts of sodium.
Resistance to these drugs is acquired very quickly if they are used alone. High serum
levels potentiate neurotoxicity manifested by lethargy, neuromuscular irritability, and
In this group of penicillins, the following preparations are found:
(a) Carbenicillin disodium (Geopen, Pyopen).
(b) Carbenicillin indanyl sodium (Geocillin).
Ticarcillin disodium (Ticar).
Azlocillin Sodium (Azlin).
e. Broad-Spectrum Antipseudomonal Penicillin with Activity
(1) This penicillin has properties similar to those of the natural penicillins.
They possess the same bactericidal activity as carbenicillin; in addition, they are
effective against Klebsiella. Some agents are more active against Pseudomonas than
(2) These drugs can be found as mezlocillin (Mezlin), or piperacillin
(Pipracil) which is the most active of all the penicillins against Pseudomonas.
a. These drugs have their origin in Cephalosporium acremonium, a fungus. This
fungus contains three antibiotics of which cephalosporin C has the most promise for
chemical modification. These modifications have proliferated to include three
generations currently on the market and a fourth being prepared for marketing.
b. The action of the cephalosporins is similar to the penicillins, and they are