Тикарциллин

Описание

Temocillin disodium is a broad-spectrum, β-lactamase resistant, injectable penicillin. High serum levels and a five hour half-life allow once or twice-daily dosing.

Определение

ChEBI: A penicillin compound having a 6beta-[(2R)-2-carboxy-2-thiophen-3-ylacetyl]amino side-group.

Антимикробная активность

Because it is hydrolyzed less rapidly than ampicillin, non-β- lactamase-producing strains of N. gonorrhoeae, ampicillin-susceptible H. influenzae and some Enterobacteriaceae are susceptible. Most aerobic and anaerobic Gram-positive bacteria are susceptible, with the exception of E. faecalis and β-lactamase-producing Staph. aureus. Anaerobic Gram-negative bacteria including B. fragilis are usually susceptible. Bactericidal synergy with aminoglycosides is demonstrable against Ps. aeruginosa and enterobacteria.

Приобретенная устойчивость

Ticarcillin is generally cross-resistant with carbenicillin. It is somewhat stable to hydrolysis by AmpC-mediated β-lactamases of Gram-negative bacilli, but can be hydrolyzed by most other chromosomally and plasmid-mediated enzymes unless protected by a β-lactamase inhibitor.

Фармакокине?тика

Oral absorption: Negligible
C_max 1 g intramuscular: 35 mg/L after 1 h
Plasma half-life: 1.3 h
Volume of distribution: 0.21 L/kg
Plasma protein binding: 50–60%
Absorption and distribution
It is not orally absorbed. On parenteral co-administration with gentamicin, the plasma concentration of ticarcillin is unaffected, but the concentration of gentamicin is lowered. It enters the serous fluids, providing concentrations up to 60% of those of the plasma. It does not cross the normal meninges but levels of up to 50% of those of the plasma can be found in meningitis.
Metabolism and excretion
Up to 15% is excreted as penicilloic acid, a higher percentage than for carbenicillin (up to 5%). Some is excreted in the bile, producing levels 2–3 times those in the plasma, but the main route of excretion is through the kidneys (80%), principally as unchanged drug, appearing in the urine in the first 6 h. It is more rapidly eliminated in children with cystic fibrosis.

Клиническое использование

Serious infection, including septicemia, respiratory tract infections, genitourinary tract infections and skin and soft-tissue infections caused by susceptible bacteria

Побочные эффекты

As with all penicillins, hypersensitivity reactions may occur, but are less frequent and severe than those associated with benzylpenicillin. Rashes and eosinophilia occur; reversible abnormalities of liver function can develop. Since large doses of the drug have to be used, convulsions can occur, as with other penicillins, and being a disodium salt, electrolyte disturbances can result from the sodium load and from loss of potassium.