Introduction to Pharmacology Flashcards
The science which deals with the study of drugs and their interactions with living organisms.
Pharmacology
Derived from the greek word pharmacon meaning drug and from the Latin word logos meaning to study.
Pharmacology
The art and science of preparing, compounding, and dispensing of drugs.
Pharmacy
The study of the source of drugs.
Pharmacognosy
The study of drug dosages.
Posology
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Study of how drugs produce effects on living organisms. Studies the mechanism and site of action of drugs.
Pharmacodynamics
The study of the processes and factors which determines the amount of drugs at the sites of action at various times between the application or administration of drugs in the body and their elimination from the body.
Pharmacokinetics
The study of weights and measures of drugs.
Metrology
This study the movement of drugs in the body including the process of absorption, distribution, localization in tissues, biotransformation and excretion.
Pharmacokinetics
The mechanism by which a drug produces an effect. Refers to where and how the effect is produced.
Drug action
When drugs bind to molecules in some sites in the body and do not produce any perceptible effect.
Non-specific drug action
Example: Acetylcholine binds to Muscarinic and Nicotinic receptors.
Drug action
When the interaction of drugs with receptor molecules produces perceptible changes in the function of an organism.
Specific drug action
The change the drug produces in an individual that can be perceived and measured.
Drug effect
Example: Acetylcholine- stimulation of smooth muscles of the viscera, increased secretion of smooth muscles.
Drug effect
drug induced change in an organism.
Pharmacological effect
Not drugs, but when administered in excess may produce exaggerated effects. In contrast, when given in proper amounts, these will promote and maintain normal body functions. These effects are physiologic in nature.
Food and hormones
Overdose of insulin causes
Hypoglycemia
- Ingestion of too much water which leads to
Cell swelling
mutually dependent, that is, one cannot be demonstrated in the absence of the other. Both action and effect may occur in one site, but in some instances the site of action is different from the site where the drug effect occurs.
Drug action and drug effects
study of harmful effects of drugs.
Toxicology
Example: Injection of insulin reduces the blood glucose to normal concentrations in a diabetic patient.
Physiologycal effect
effect that maintains normal body functions.
Physiologycal effect
study of the application of drugs for use in the diagnosis, prevention, and treatment of diseases.
Pharmacotherapeutics
emphasis on the chemical properties of poisons.
Chemical toxicology
emphasis on diagnosis, prevention, and treatment of poisonings with chemical substances including medicine.
Clinical toxicology
identification of substances in suspected cases of poisoning with the aim of solving a chemical problem,
Forensic toxicology
emphasis on promulgation of laws on safety of chemical substances in the environment or food for human, animal and plant population.
Legal toxicology
Categories of Pharmacology
Molecular Pharmacology
Clinical Pharmacology
Veterinary Pharmacology
concerned with the rational development, effective use, and proper evaluation of drugs for the diagnosis, prevention and cure of diseases.
Clinical Pharmacology
study of basic mechanism of drug action on biological systems.
Molecular Pharmacology
concerned with drugs as they are used in the diagnosis, treatment of animal diseases, and in the intentional alteration of animal physiology.
Veterinary Pharmacology
Treatment consisted of attempting to balance these humors by replenishing of deficiencies or removing excesses. Thus drove the practices of bleeding, purging (including vomiting) and sweating that continued well in the 19th century.
Hippocrates
The earliest written compilation of drug written by Emperor Shenung in about 2700 BC.
Pen Tsao
The oldest record of Egyptian drug codification written about 2000 BC. which deals with veterinary medicine and uterine disease of women and contains a number of prescriptions.
Kahun Papyrus
The four elements of philosophy were; water, fire, air and earth. Combinations of these elements gave rise to four humors of the body related to a scale of life from most alive to death. They were blood (sanguine temperament), phlegm (phlegmatic), yellow bile or urine ( bilious), and black bile (melancholic).
Hippocrates
Greek physician (400-375 BC.) Great teacher of Medicine. Adapted the notion of a humoral basis for diseases from philosophies in Asia Minor.
Hippocrates
(384 – 322 BC), begun the scientific basis of medicine who made and recorded numerous observation on animals.
Aristotle
(380-270) pupil of Aristotle. He systematically classified medicinal plants in the basis of their individual characteristics rather than their recommended use in treatment.
Theophrastus
A surgeon who improved the work of Theophrastus and who compiled the first Materia Medica which consisted of six volumes describing about 600 plants. Drugs were discussed from the standpoint of name, source, identification, tests for adulteration, preparation of the dosage form, what it would do and what conditions would be used.
Dioscorides
Officialy recognized books of drug preparation.
Pharmacopeias
(131 – 200), his work dealing with physiology and material medica became authoritive which were used widely for 1400 years.
Galen
Developed the practice of pharmacy to a high level and was the first to distill wines and beers to obtain ethanol for preparing tinctures. They were also the first to regulate the practice of pharmacy to standardize the preparation of prespcriptions.
Muslim cultures
(702 - 765) classified drugs and poisons and recognized that the difference between a drug and a poison was a matter of dosage. Any drug can be toxic if given in large amounts.
Geber Ibn Hagar
(1493 - 1541) introduced the clinical use of laundanum (opium) and a number of tinctures of various plants.
Theophrastus Bombastus von Hohenheim
(1514 - 1544) compiled the first pharmacopeia and described techniques to be employed in preparation of drugs.
Valerius Cordus
(1741 - 1799) gave the most notable contribution to therapy an account of the Foxglove and some of its medical uses. His observation on the usage of digitals is the treatment of dropsy (ascites due to CHF) are steel pertinent.
William Withering
Drugs such as crichona (quinine), coffee, tea and cocoa (methylxanthines), curane, digitalis, and a variety of alkaloids were discovered.
17th ad 18tht Century
(1749 - 1823) discovered and established the principle of prophylactic immunization against small pox and was the first to describe anaphylaxis.
Edward Jener
(1578 - 1657) discovered the circulation of blood.
William Harvey
(1632 - 1723) made the first intravenous injections of drugs into a dog.
Christopher Wren
(1871 - 1884) devised the first hypodermic needle and syringe.
Alexander Wood
The science of pharmacology has flourished in the medical and pharmacy schools. The ability of chemists in the pharmaceutical industry to synthesize new chemical substances has removed our dependence on natural products as source of drugs.
20th Century
was instrumental in shifting emphasis in the veterinary curriculum form material medica to the Science of Veterinary pharmacology.
L Meyer Jones
Opened the first school of veterinary medicine in Lyons on February 13, 1762.
Claude Bourgelat
Produces in 1932 effective against bacterial diseases which led to the significant improvement in animal welfare. This were followed by the introduction of penicillin.
Sulphonamides
In 1960 was discovered for parasite therapy. The first was thiabendazolel.
Benzimadazoles
Products that have been authorized by Agricultural and health ministers.
Veterinary medicine
is any drug or substance with specific affinity to a receptor. Receptors are molecules to which a drug has specific affinity.
Ligand
2 requirements for drug activity
Affinity and Efficacy
tendency of a drug to combine with its specific receptor.
Affinity
inherent capacity of a drug to produce a response by itself.
Efficacy
A drug with affinity but without intrinsic activity may produce a
Physiological Change
a drug that does not have intrinsic activity but binds with specific receptors.
Antagonist
a drug having both agonistic and antagonistic properties
Dualist
cannot produce an effect except in the presence of an agonist.
Competitive Antagonist
inhibits the action of an agonist by binding at a site other than the receptor.
Non competitive Agonist
a function of the drug’s affinity for the receptor, absorption, excretion, degradation rates.
Potency
in the same patient can be due to circadian changes, age, state of health, drug – indeed.
Variability
indicates the range of dosage over which the drug acts, from minimally detectable to maximally effective.
Slope
The body reservoir that holds the greatest amount of the barbiturate thiopental is
Fat
Features of dose response curves
Potency, slope, variability
Body fat may contain up to -__________ of an administered dose of lipid soluble thiopental _________ after injection.
70%, 3hours
when one of the two drugs has zero intrinsic activity. The drug with zero intrinsic activity is considered a potentiator.
Potentiation
effect of a drug combination is greater than the separate effects of the individual drugs.
Synergism
Drugs are usually released much more slowly from fat because
Fat has relatively blood supply
the combined effect of the drugs is equal to the sum of their individual effect.
Additive Effect
results from coulombic forces ( electrostatic attraction ) between oppositely charged ions. The force of attraction between ions diminishes inversely with the square of the distance between them.
Ionic bond
two atoms share a pair of electrons. It has high binding energy. can be broken at very high temperature or intervention of catalytic enzymes.
Covalent bond
The most dangerous route of drug administration. Although it has many advantages.
IV route
In the oral administration of drugs, absorption occurs mostly in
duodenum but in some cases may also occur in the mouth, stomach, and colon.
Examples of parental route of drug administration
Intravenous
subcutaneous
intrapleural
intrasynovial
intraconjunctival
intratracheal
intramuscular
intraperitoneal
intraarterial
inhalation
intranasal
intradermal.
arises from the ability of a proton ( H ) to accept an electron pair. It is stronger than a covelant bond.
Hydrogen Bond (H-bond)
from very weak bond between depoles or induced dipoles, often between similar atoms.
Intermolecular forces (van der Waals forces)
injection of the drug into rumen. The enteral route includes the oral route ( by mouth, per os, per orem, p.o ) and rectal route.
Enteral
the study of the rate of change from the initial state to the final state of a substance.
Kinetics
a constant percentage of the drug remaining in the site of administration is absorbed (or disappears from the site with time )
First order Kinetics
the actual amount of drug absorbed per unit time is the same regardless of how much of the drug remains in the site.
Zero order Kinetics
the time it takes for a drug concentration to be reduced to 50% its initial concentration.
Half life
the total quantity of drug absorbed intact.
Bioavailability
Fluid compartments of the body
Blood / plasma - 4% body weight
Interstitial - 18% body weight
Transcellular - 2% body weight
Intracellular - 40% % body weight
when injected into the circulation stays confined to the cardiovascular system. Its volume of distribution therefore is equal to the plasma volume.
Evan’s blue or l-albumin
readily crosses all epithelial barriers. It is used to measure total body fluid volume.
Isotopic water or antipyrine
freely diffuses out of blood vessels but does not enter the cells. It therefore measures the ECF.The difference between ECF and plasma volume is the interstitial fluid volume.
Inulin or EDTA
are extracellular fluids but enclosed within epithelial tissues. They include synovial, intraocular, cerebrospinal, peritoneal, pericardial, and pleural fluids.
Transcellular fluid volume
inactivation of most drugs.
Biotransformation
removal of drug and drug metabolities from the body.
Excretion
terminated drug activity by removing the drug from its site of action into other sites within the body. The sequestered drug will be eventually biotransformed and excreted.
Redistribution of sequestration
refers to the biochemical processes affecting the pharmacological activity of drugs and other substances.
Biotransformation
reduction of drug activity.
Detoxification
normal anabolic and metabolic reactions ex. Hormones
Metabolism
the process of transforming and inactive or less active compound to a more active metabolite but the resulting does not always cause death.
Lethal synthesis
The most important site of drug biotransformation in the body, but biotransformation also occurs in other organs including the intestinal mucosa, lungs, and kidneys.
Liver
generally less active than the parent compound if not totally inactive. _________ or by products are almost always more polar and less soluble than the parent compound.
Metabolities
The microsomal enzymes also known a ________, are a complex of proteins and heme which are located in the SER ( Smooth endoplasmic reticulum ) wherein pieces of which are called microsomes.
cytochrome P-40 or mixed function oxidases
2 phases of Biotransformation
Phase I and Phase II
four reactions in the biotransformation of drugs by the micriosomal enzymes
oxidation
reduction
hydrolysis and
conjugation.
involves synthetic reactions conjugating the products of Phase I reactions with metabolites normally present in the body such as glucoronide, sulfate, acetate, and ornithine.
Phase II
Reductive reaction
Azo reduction, Nitro reduction
Oxidative Reactions
Aromatic hydroxylation
aliphatic oxidation
O-dealkylation
N-dealkylation
oxidative deamination, desulfuration
sulfoxidation
Hydrolytic reaction
Easter hydrolysis, nitro reduction
Conjugation reaction
glucoronic acid conjugation
sulfate conjugation
acetylation
methylation
the most important means of eliminating drugs from body
Urine Bile
