[Pharmaceutical aspects of creating an effective drug form of carfecillin]. / Farmatsevticheskie aspekty sozdaniia éffektivnoi lekarstvennoi formy karfetsillina.

Physical and technological parameters of carfecillin powder and carfecillin with auxiliary substances in the form of the powder mixture and granulate were studied comparatively. Possible preparation of carfecillin capsules characterized by high levels of the antibiotic dissolution was shown.

[Effect of carfecillin on the body of animals in single and multiple administrations]. / Izuchenie vliianiia karfetsillina na organizm zhivotnykh pri odno- i mnogokdratnom vvedenii.

The effect of carfecillin on blood circulation, respiration, hepatic and renal functions, peripheral blood picture, growth and development of young animals was studied in acute and chronic experiments. The allergizating properties of the drug were also investigated. Carfecillin is low toxic. LD50 for albino mice on intravenous and oral administration of the drug is 782.5 and 3924 mg/kg respectively. When used repeatedly for treatment of rats in oral doses of 180 and 275 mg/kg corresponding to the daily doses for humans calculated for the body surface, carfecillin had no adverse effect on hepatic or renal function, cell composition of the blood, augmentation of the weight and relative weight of the organs of the growing animals. No detectable effect of carfecillin on arterial pressure, respiration, rhythm and amplitude of the systole was observed in acute experiments with anesthetized cats treated with the antibiotic intravenously in doses of 320 mg/kg. Histological examination of the internal organs of the rats treated with oral carfecillin during 2 months showed that the drug had an irritating effect on the gastrointestinal mucosa only in a dose of 540 mg/kg, which is 2 times higher than the equivalent daily dose for humans. Carfecillin possesses the allergizating properties and induces development of cross allergy to benzylpenicillin. The above properties were less pronounced in carfecillin than in benzylpenicillin.

[Pharmacokinetic and clinical research of a new phenyl ester of carbecinillin: carfecillin]. / Ricerca farmacocinetica e clinica su un nuovo estere fenilico di carbenicillina: carfecillina.

Following a review of the latest methods of treating infections of the urinary ways, the pharmacokinetic and clinical results of a new antibiotic, Carfecillin, are reported. The examination was carried out on a total of 10 volunteers. The substance showed good serum levels and fair renal excretion with both the 250 mg and the 500 mg p.o. doses. The clinical study was carried out on a double blind basis versus a standard reference (indanyl ester of carbenicillin) in 26 patients and showed the electivity of the antibiotic in the oral treatment of urinary infections under well tolerated conditions.

Carfecillin: antibacterial activity in vitro and in vivo.

Carfecillin, the alpha-phenyl ester of carbenicillin, hydrolyses rapidly in the presence of serum or body tissues to liberate carbenicillin but hydrolysis is less rapid in aqueous solution. The activity of carfecillin in antibacterial tests in vitro depends upon the extent of hydrolysis to carbenicillin, and in conventional serial dilution tests carfecillin shows an antibacterial spectrum generally similar to that of carbenicillin due to extensive hydrolysis. However, in tests in which the extent of hydrolysis is reduced, carfecillin displays lesser activity than carbenicillin against gram-negative bacilli and greater activity against gram-positive cocci. In the presence of serum carfecillin is hydrolysed rapidly to carbenicillin and the activity shown is solely that of carbenicillin. Unlike carbenicillin, carfecillin is well absorbed in mice after oral administration, producing significant carbenicillin blood concentrations and the compound is as effective by the oral route in the treatment of various experimental mouse infections as is parenteral carbenicillin.