Subject(s)
Drug Therapy/history , Pharmacokinetics , Absorption , Algorithms , Biological Availability , Directed Molecular Evolution/history , Directed Molecular Evolution/methods , Drugs, Generic/history , Drugs, Generic/pharmacokinetics , Drugs, Generic/therapeutic use , Genetic Therapy/history , History, 20th Century , Models, Chemical , Pharmaceutical Preparations/chemical synthesis , Pharmaceutical Preparations/history , Phytotherapy , Plants, Medicinal/therapeutic use , Recombinant Proteins/history , Research , Therapeutic EquivalencyABSTRACT
The response obtained to drug administration can be modified by several factors which, from a synthetic point of view, can be classified into four basic groups: physical, chemical, biological and therapeutical. The first two can be verified and controlled by means of in-vitro test and, they must be known and solved before de final formulation is obtained. The other two factors, biological and therapeutical ones, introduce variables whose analysis concerns to the prescriptor. After this introduction, the variability in drug response is analyzed and discussed paying special attention to the pharmacokinetic and pharmacodynamic variability, analyzing the sources of such variability: environmental factors, factors depending of age, physical and genetical constitution, pathological states or drug interactions.
Subject(s)
Drug Therapy , Aging/drug effects , Body Constitution , Chronotherapy , Dose-Response Relationship, Drug , Drug Administration Routes , Humans , PharmacokineticsABSTRACT
In this work, the swelling index is determined for various vegetable fibers (wheat bran. orange fibre and lemon fibre), and several granulated formulations to which different binding agents are added. The formulation that presents the highest swelling index (14.5 ml/g) was found to be composed of orange fibre, lemon fibre and pectin in a 1:1:1 proportion (OF + LF + PH). A study of the evolution of the swelling with time is also carried out, finding that the greatest volume increase is produced between 5 and 10 min from the start of the test. The application of the sigma-minus type calculation to the swelling rate curves produces correlation coefficients higher than 0.9. It is found that the swelling rate constant for lemon fibre is much lower than that of orange fibre. The addition of pectin lowers the swelling rate constant while the gum guar and polyvinylpyrrolidone increase the said constant. In addition, a general exponential equation is deduced which can be applied to all of the cases studied.
Subject(s)
Cathartics/administration & dosage , Cathartics/chemistry , Plants , Chemical Phenomena , Chemistry, Pharmaceutical/methods , Chemistry, Physical , Water/chemistryABSTRACT
The transfer process of salicylic acid through a cellophane membrane is studied. The active component is formulated as a semisolid emulsion (O/W) for external local application. Different theoretical mathematical models are applicable to the experimental data obtained in order to find the mathematical expressions which define the transfer kinetics. Later on, comparative studies of these mathematical models are carried out in order to choose the one which better defines the whole transfer process.
