ABSTRACT
Pharmacokinetics of rifampicin after its single intratracheal administration in the form of the liposome-encapsulated drug and its aqueous solution was studied on rats. It was shown that after the exposure to the liposome-incorporated rifampicin (10 mg/kg) the concentration-time curve in the blood and lungs was sigmoid with the retarded decrease in the blood drug concentration within 9 hours. The plateau segment of the curve provided at least a 4-fold longer maintenance of the rifampicin concentration in the blood and lungs at 3 to 4 micrograms/ml. The use of the liposome-incorporated antibiotic induced 2- and 1.5-fold increases in the AUC in regard to the lungs and blood, respectively.
Subject(s)
Liver/metabolism , Lung/metabolism , Models, Biological , Rifampin/analogs & derivatives , Rifampin/pharmacokinetics , Animals , Catheterization, Peripheral , Drug Carriers , Liposomes , Rats , Rifampin/administration & dosage , Rifampin/blood , Time Factors , Trachea/drug effectsABSTRACT
It was shown that detergent dialysis could be successfully used for liposomal encapsulation of substances belonging to different chemical groups with diverse therapeutic activity such as rifampicin, aclarubicin, amphotericin B, pefloxacin and insulin. Liposome encapsulation of substances poorly soluble or insoluble in aqueous media was likely the most promising. The optimal incorporation depended on both the composition of the lipids forming the liposomes and the properties of the compounds being encapsulated.
Subject(s)
Anti-Bacterial Agents/administration & dosage , Insulin/administration & dosage , Cholesterol/administration & dosage , Drug Carriers , Emulsions , Flow Injection Analysis/methods , Liposomes , Phosphatidylcholines/administration & dosage , Russia , Stearic Acids/administration & dosage , Vitamin E/administration & dosageABSTRACT
Rifamethoprim is a new formulation containing rifampicin and trimethoprim. Its efficacy was studied in the treatment of a group of patients with various nonspecific diseases of the lungs. It was shown to be highly active against a broad spectrum of pathogens. With inclusion of trimethoprim to the formulation it appeared possible to markedly lower the bacterial ability to develop resistance to rifampicin, which solved the problem of long-term antibiotic use. The unique pharmacokinetic properties of rifampicin such as its capacity to penetrating into the sputum, lung tissues and cells make rifamethoprim be the drug of optimal choice in the treatment of respiratory diseases.
Subject(s)
Anti-Bacterial Agents , Bronchial Diseases/drug therapy , Drug Therapy, Combination/therapeutic use , Lung Diseases/drug therapy , Rifampin/therapeutic use , Trimethoprim/therapeutic use , Acute Disease , Chronic Disease , Drug Combinations , Drug Therapy, Combination/pharmacokinetics , HumansABSTRACT
The rate of cephalexin release from various dosage forms such as tablets, capsules and suspensions manufactured by several firms was studied. In vivo studies showed that pharmacokinetic indices of the absorption depended on the rate of cephalexin release from the dosage forms. The proposed procedure for in vitro estimation of the cephalexin release rate reflects bioavailability of the antibiotic dosage forms and may be used in quality control of finished dosage forms.
Subject(s)
Cephalexin/pharmacokinetics , Animals , Biological Availability , Biopharmaceutics , Capsules , Cephalexin/administration & dosage , Dogs , Powders , Solubility , Suspensions , Tablets , Time FactorsABSTRACT
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.
Subject(s)
Carbenicillin/analogs & derivatives , Carfecillin/pharmacology , Capsules , Carfecillin/administration & dosage , Chemistry, Pharmaceutical , Powders , Solubility , TabletsABSTRACT
Soviet doxycycline capsules in a dose of 0.1 g were studied in vitro (for disintegration and solubility) and in vivo (pharmacokinetics on 25 patients). It was found that Soviet doxycycline capsules provided comparatively rapid absorption of doxycycline. The antibiotic availability may be characterized by the solubility test. The results of the study on bioavailability of Soviet doxycycline capsules were compared with the results of analogous studies published by American authors for doxycycline capsules manufactured by various firms of the USA.
Subject(s)
Doxycycline/metabolism , Absorption , Administration, Oral , Adult , Biological Availability , Capsules , Clinical Trials as Topic , Female , Humans , In Vitro Techniques , Kinetics , Middle Aged , Solubility , Time FactorsABSTRACT
Desintegration and dissolution of capsules and tablets of methacycline hydrochloride were studied. The study on solubility of methacycline hydrochliride capsules filled with methacycline granulate or powder according to the same formula showed that the rate of the antibiotic liberation from the capsules filled with the powder decreased during storage while that from the capsules filled with the granulate did not change. Investigation of the effect of the mass packing value in a drop on the antibiotic liberation from the capsules showed that an increase in the packing coefficient above 1.38 resulted in a marked decrease in the rate of methacycline liberation from the capsules filled with the granulate. No correlation between desintegration and dissolution of methacycline capsules and tablets was found.
