Pharmacokinetics of drugs Pharmacokinetics is the study of the actions of the drugs in the body over a defined period of time. It deals with the absorption, distribution, biotransformation and excretion of the drug. Pharmacokinetics is ‘what the body does to the drug’. Importance of kinetic study For arriving at the dosage regimen (dose amount and dosing […]
Passage of drug across biological membrane Passive diffusion Passive diffusion is a random movement of drug molecules from an area of higher concentration to an area of lower concentration. When a drug is injected into the body, it passively diffuses from the injection site to areas of lower concentration, eventually reaching a blood capillary and entering
Structure of biological membranes in animals Fluid mosaic model Biological membranes may be viewed as mosaics of functional units composed of lipoprotein complex. Most membranes are composed of a fundamental structure called the unit membrane or plasma membrane, that is 80 to 100 Aο thick, surrounds single cells and nuclei. Complex barriers such as the intestinal epithelia and
Route of Drug administration in animals Routes of drug administration can be divided into three main classes as enteral, parenteral and topical. Enteral administration refers to administration of drugs via the gut. Parenteral (par – beyond, enteral – intestinal) administration covers intravenous, intramuscular, subcutaneous, intraperitoneal etc. and Topical application refers to application of drugs on the skin and
Natural Sources of drugs in pharmacology There are various sources of drugs available in nature such as plants, animal and minerals. in this article we will discuss about Natural and microbial source of drugs. Plant sources of drugs Many drugs available from plants are even today used in the treatment of pathological conditions. With the
Pharmacology related terms Pharmacology is the science that embraces the knowledge of the history, source, physical and chemical properties, compounding, biochemical and physiological effects, mechanism of action, absorption, distribution, biotransformation and excretion of drugs. It is also defined as an experimental science dealing with the properties of drugs and their effects on living system. Pharmacodynamics Pharmacodynamics is
Scope and Branches of Pharmacology Scope of Pharmacology Pharmacology is the science which involves all aspects of the action of drugs on living system. It is the study of the therapeutic value and/or potential toxicity of chemical agents on biological systems. It targets every aspect of the mechanisms for the chemical actions of both traditional and
History of Pharmacology History of Pharmacology can be divided in these five Eras- Ancient medicine era Pre-Christian era Mediaeval medicine era Revolts medicine era Modern medicine era 1. Ancient medicine era Chinese medicine is the earliest and records dated about 2500 B.C. available today give an idea about the medical knowledge of Chinese. In Chinese
Regulation of respiration in birds Respiratory centres as are as in mammals, Chemoreceptors are also important for regulation of respiration in birds Most of these receptors are present in lungs and they detect CO2 levels in lungs and not of blood. They are stimulated by low CO2 level and once stimulated they reduce respiration. The central chemoreceptors
Airsacs and Mechanism of respiration in birds The lungs are small and attached to ribs and are rigid; they do not expand or contract during the respiratory cycle. Large discrete air sacs are present. Both inspiration and expiration are active. Respiratory system beginning from external nares leads to nasal cavities, which open into pharynx. The
