Introduction to Pharmacology Flashcards
These are poisons of biologic origin
toxins
Study of substances that interact with living systems through chemical processes especially by binding to regulatory molecules and activating or inhibiting normal body processes
Pharmacology
These are drugs that have almost exclusively harmful effects
Poisons
Pharmacology is the basic knowledge concerned with the action of:
chemicals on biologic systems
Branch of pharmacology that deals with the undesirable effects of chemical on living systems, from individual cells to human to complex systems
Toxicology
This speaks of what the drug does to the body
pharmacodynamics
Science of substances used to prevent, diagnose, and treat diseases
Medical Pharmacology
This speaks of what the body does to the drug
pharmacokinetics
Pharmacodynamics is also known as the ___________ of the drug
Mechanism of action (MOA)
This major drug-receptor bond is important in the interactions of highly lipid-soluble drugs with the lipids of cell membranes and perhaps in the interaction of drugs with the internal walls of the receptor “pockets”
hydrostatic interactions
What major type does the acetyl group of aspirin use to bond with COX to effectively barricade the COX active site and block the synthesis of COX-2?
covalent bond
**3 major bonds:
Covalent bonds
Electrostatic bonds
Hydrophobic interactions
These are the components of discussion for pharmacokinetics (4)
Absorption
Distribution
Metabolism
Excretion
of the drug
This is any substance that brings about a change in biologic function through its chemical actions
Drug
This is a specific molecule that drugs interact with in biologic system that plays a regulatory role
receptor
True or False: (give rationale)
Drugs that bind through weak bonds to their receptors are generally more selective than drugs that bind by means of very strong bonds
False:
Drugs that bind through weak bonds to their receptors are generally more selective than drugs that bind by means of very strong bonds
→ Rationale: weak bonds require a very precise fit of the drug to its receptor if an interaction is to occur.
This is the first line treatment for a certain disease
Drug of Choice (DOC)
This term also pertains to DOC in that it is the best treatment option for the disease based on affordability, safety, sustainability, and efficacy
Rational drug use (RDU)
What event brings about the effects of drugs?
drug-receptor interactions
This is any article used in the mitigation, diagnosis, prevention, and cure of disease in man and in animals
drug
These are specific molecules in a biologic system with which drugs interact to produce changes in the function of the system
receptors
In order to respond to the proper chemical signal, receptors should be _________ in ligand-binding characteristics
selective
In order to bring about the functional change, receptors should be _________ when they bind
modifiable
This is a molecule to which a drug may bind without changing any function.
inert binding site
Plasm albumin is a nonregulatory molecule to which drugs bind, but do not result to any detectable change in the function of the biologic system; hence, it is called an:
inert binding site
This molecule to which drugs bind affects the distribution of drug within the body and determines the amount of free drug in the circulation; hence, making in a vital component of pharmacokinetics
inert
This molecule to which drugs bind affects the distribution of drug within the body and determines the amount of free drug in the circulation; hence, making in a vital component of pharmacokinetics
inert binding site
This is known as the “Law of Pharmacodynamics” that theorizes the combination of drug molecule with a receptor for which it has affinity and the initiation of the pharmacological response by intrinsic factors
Drug- Receptor Occupancy Theory
This theory states that there exist receptors if maximal drug response (Emax) is obtained at less than maximal occupation of the receptors (Bmax)
Spare receptor theory
What is the nature of receptor (according to location) for anesthesia and beta-blockers?
intracellular
What are the two types of drug receptors according to location?
Intracellular and Extracellular
What are the types of drug receptors according to function?
Enzymes
Regulatory
Transport/Channel
Structural
Orphan
What type of drug receptor according to function make up most of the receptors?
enzyme receptors
What type of drug receptors according to function do NSAIDs inhibit?
enzyme:
cyclooxygenase - to prevent the formation of PGs which are mediators of pain and inflammation
Ranitidine blocks what type of drug receptor according to function?
Regulatory:
H2 (histamine receptor 2 - gastric mucosa) - prevents release of H2 from gastric mucosa to prevent production of gastric acids
What is the specific type of histamine receptor that functions for allergic reactions?
H1
Among the most important stabilizers are the many substances used clinically as local anesthetics, including procaine and tetracaine. Most of these agents act directly on the activation gates of the sodium channels, making it much more difficult for these gates to open and thereby reducing membrane excitability. Hence, these drugs are of the type:
Regulatory
Vinca alkaloids act upon tubulin by preventing it from forming into microtubules; hence, preventing cell division. These drugs, therefore, are of the type:
structural
Mebendazole and colchicine act on the drug receptor type:
structural:
Mebendazole (anti-helminthic) - inhibits microtubule formation
Colchicine (anti-gout) - alters the movement of cells like neutrophils
These are drug receptors of unknown ligands and are useful targets for future drug development
orphan receptors
This pertains to the combining of a drug molecule with the receptor for which it has affinity, and the initiation of a pharmacologic response by its intrinsic activity
drug-receptor interaction
What are the 3 requirements of drug-receptor interaction?
Well-fitted
Highly specific
Definite
This pertains to the activity of receptors in the absence of ligands
constitutive activity
This is a drug capable of fully activating the effector system when it binds to the receptor
Full agonist
This is a drug that produces less than the full effect, even when it has saturated the receptor
Partial agonist
True or False:
In the presence of a full agonist, a partial agonist acts as an inhibitor
True
These drugs bind with equal affinity to the inactive and active receptor states and prevent binding by an agonist and preventing any deviation from the level of constitutive activity
Neutral antagonists
These drugs have a higher affinity for the inactive receptor state than for active receptor and decrease or abolish any constitutive activity
inverse agonist
True or False:
Antagonistic drugs have intrinsic activities
False
Antagonist has affinity to the receptor but no intrinsic activity.
Its primary action in to reduce the effects of agonists that normally activate receptors
This type of antagonist interaction has weak attraction of the ligand and the receptor; hence, easy dissociation
Reversible
(temporary inhibition)
This type of antagonist interaction involves covalent binding and reduces Emax, but not necessarily EC50
Irreversible
This type of antagonist surmountability overcomes the effect of the antagonist by increasing the dose of the agonist
Competitive
This type of antagonist surmountability does not allow the agonist to surmount the inhibitory effect once the receptor is bound the drug irrespective of agonist’s concentration
Noncompetitive
The degree of inhibition produced by a competitive antagonist depends on:
the concentration of antagonist
Clinical response to a competitive antagonist also depends on the concentration of ________ that is competing for binding to receptors
agonist
This is a positively charged non-drug chemical that is used as antidote for heparin poisoning by acting via ionic binding to inactivate the anticoagulant property
protamine sulfate
Nature of antagonism: Chemical
This type of antagonism according to nature cancels the end effects
Physiologic
This drug results to competitive full effects for morphine (an opioid agonist)
naloxone (opioid antagonist)
Pharmacologic interactions that occur when the combined effect of two drugs is greater than the sum of their effects when given separately
Synergism (1+1 = 11)
Pharmacologic interactions that occur when one drug does not elicit a response on its own but enhances the response to another drug.
Potentiation (1+0= >1)
What type of diet should not be recommended for patients with decreased Fe or Ca absorption?
High vegetable diet that decreases Fe & Ca absorption by acting as chelators of the metal ions
This juice is an inhibitor of CYPP450 which leads to decreased metabolism of some drugs
grapefruit juice
This is an herb that increased the metabolism of digoxin via CYP induction which decreased its effects
St. John’s Wort
This pertains to the relationship between a drug’s molecular structure and the drug’s biological activity
Structure Activity Relationship (SAR)
This is the concentration of drug that produces 50% of maximal effect
EC50
half maximal effect concentration
This pertains to the peak effect/ maximal response that can be produced by the drug
Emax
Symbol for dissociation constant
Kd
This represents the concentration of free drug at which half-maximal binding is observed
Kd; dissociation constant
This pertains to the total concentration of receptor sites (i.e., sites bound to the drug at infinitely high concentration of free drug)
Bmax
This refers to the plateau portion of the curve or the constant peak effect or the situation wherein the overall intake of a drug is fairly in equilibrium with its elimination
Steady-State Concentration (SSC)
It is generally considered that steady state is reached when a time of ___________ is achieved for a drug after regular dosing has started
4 half-lives