Comparative in vitro activity and clinical pharmacology of ticarcillin and carbenicillin.
The in vitro activity and human pharmacology of ticarcillin, a semisynthetic penicillin more active than carbenicillin against Pseudomonas, were compared. There has been no increase in resistance to ticarcillin of Pseudomonas strains over the past 5 years, but resistance of indole-positive Proteus and Serratia strains has been documented. After intramuscular (i.m.) injection of 1 g of ticarcillin, mean peak levels occurred at 1 h (26.9 mug/ml) with a decline over 6 h (6.8 mug/ml). Serum half-life was 84 min. Dilution of ticarcillin lidocaine reduced pain on i.m. injection but did not alter serum levels. Blood levels after 1 g i.m. are adequate to treat infections produced by Escherichia coli, Proteus mirabilis, and some Enterobacter, but not Pseudomonas. After rapid intravenous infusion of 3 and 5 g, mean peak serum levels of ticarcillin were slightly lower for 1 h than those achieved with carbenicillin. Probenecid administered before infusion produced increases in blood levels, half-lives, and volume of distribution. The biological half-life of ticarcillin was 72 min compared to 66 min with carbenicillin. There was a larger volume of distribution for ticarcillin than carbenicillin (15 liters versus 14 liters). The ticarcillin half-life when administered with probenecid was 108 min. Urinary recovery of ticarcillin was 77% against 95% of carbenicillin. However, approximately 10% of ticarcillin is recovered as penicilloic acid so that 95% of an intravenously administered dose is recovered.
D002228:Carbenicillin / Q000008:administration & dosage / Q000378:metabolism / Q000494:pharmacology*; D004755:Enterobacteriaceae / Q000187:drug effects; D006207:Half-Life; D006801:Humans; D007263:Infusions, Parenteral; D007273:Injections, Intramuscular; D008297:Male; D008826:Microbial Sensitivity Tests; D010406:Penicillins / Q000494:pharmacology*; D011549:Pseudomonas / Q000187:drug effects; D013982:Ticarcillin / Q000008:administration & dosage / Q000378:metabolism / Q000494:pharmacology*
D010406:Penicillins; D013982:Ticarcillin; D002228:Carbenicillin