Skip to main content

BCQs of Pharmacokinetics and pharmacodynamics part -2

  


Q1: Pharmacokinetics include which of the following?

        (a) Drug biotranformation in the organism

        (b) Influence of drugs of genes

        (c) Complications of drug therapy

        (d) Influence of drug on metabolism procss


   Answer ~ A



Q2: Pharmacokinetics include : 


        (a) Interaction of substances

        (b) Localization of drug action

        (c) Mechanism of drug action

        (d) Excreation of substances


    Answer ~ D



Q3: Pharmacokinetics include : 


        (a) Unwanted effects of drugs

        (b) Pharmacological effects of drugs

        (c) Distribution of the drug in the organisms

        (d) Chemical structure of medical agent


   Answer ~ C



Q4: Which kind of substances can not cross membrane by passive diffusion ?


        (a) Hydrophobic substances

        (b) Hydrophilic substances

        (c) Non-ionized substances

        (d) Lipid soluble



    Answer ~ B



Q5: Pharamcokinetics parameter that reflects the effects of various factors on distribution of drug in body is: 


        (a) Realative volume of distribution

        (b) Absolute volume of distribution

        (c) Bioavailability

        (d) Apparent volume of distribution



    Answer ~ A




Q6: Favourable route of administration for heparin is: 


        (a) Oral

        (b) Intravenous

        (c) Intramuscular

        (d) Topical

        (e) Subcutaneous



     Answer ~ E




Q7: Hydrophilic medicinal agent has the following property : 


        (a) Low ability to penetrates through cell membrane

              lipids

        (b) Easy permeation through blood brain barrier

        (c) High reabsorption in renal tubules

        (d) Penetrates through membrane by means of 

              endocytosis



    Answer ~ A




Q8: “Bioavailability” is the term which means :


        (a) Permeability through blood brain barrier

        (b) Plasma protein binding the drgree of substance

        (c) Fraction of the deug that reaches general circulation in unchanged form. 

        (d) Amount of substance in urine relative to initial dose. 


     Answer ~ C




Q9: Which is true regarding bioavailability : 


        (a) Ratio of amount of drug administered to amount absorbed in systemic circulation. 

        (b) Ratio of amount of drug absorbed in portal circulation to amount administered.

        (c) Ratio of amount of drug eliminated to amount

adminstered. 

        (d) Ration if amount of drug metabolised to amount

administered. 

        (e) Ratio of amount of drug absorbed in systemic circulation to amount adminstered. 



    Answer ~ E



Q10: Regafing bioavailability all are true except : 


        (a) It is the ratio of amount of drug absorbed in systemic circulation to amount administered. 

        (b) Bioavailability of intramuscular ratio is less than intravenous route. 

        (c) Different administration route have their respective bioavailability. 

        (d) Two drugs have similar bioavailability when adminstered orally. 



    Answer ~ D




Q11: Reasons for determinig bioavailability are : 


        (a) Extent of absorption and hepatic first pass effect

        (b) Glomerular filteration rate

        (c) Rheological parameter of drug

        (d) Amount of substance obtained orally and quantity of intakes. 



   Answer ~ A




Q12: Parental  administration :


        (a) Can’t be used with unconscious patient

        (b) Is too slow fro emergency use

        (c) Generally resukt in less accurate dosage than oral administration. 

        (d) Usually produce more rapid response than oral administration. 



     Answer ~ D




Q13: Parental route of drug administartion is :


        (a) Intrathecal

        (b) Sublingual

        (c) Oral

        (d) Rectal



    Answer ~ A




Q14: What is the characteristics of intramuscular route of drug administration? 


        (a) Oily solutions can be injected

        (b) Only water solution can be injected

        (c) Hypertonic solution injections

        (d) The action develops slower than oral 

               administration. 



      Answer ~ A




Q15: Which of the following is not Biological barrier :


        (a) Cell membrane

        (b) Capillaries

        (c) Renal tubules

        (d) Placenta



      Answer  ~ C




Q16: Component if biological system to which drug binds to bring about change in function of system is : 


        (a) Receptor

        (b) Effector

        (c) Spare Receptor

        (d) Inner binding site



      Answer ~ A




Q17: Component of the biological system to which drug binds without changing in function of it’s : 


        (a) Spare receptor

        (b) Inner binding site

        (c) Effector

        (d) Transport channel

        (e) Enzymes



    Answer ~ B




Q18: The volume of distribution(Vd) relaltes :


        (a) An administered dose in body weight

        (b) Single to a daily dose of an adminstered drug

        (c) The uncharged drug reaching the systemic circulation. 

        (d) The amount of drug in the body to the concentration of drug in plasma. 



     Answer ~ D




Q19: Biotransformation means : 


        (a) Process of physiochemical and biochemical alteration of drug in body. 

        (b) Binding of substance with plsma protein

        (c) Accumulation of substance in fat tissue

        (d) Accumulation of substance in tissue



     Answer ~ A




Q20: An antagonist is the substance that: 


        (a) Bind to receptor and initiates changes in cell 

               function, producing maximal effect. 

        (b) Binds to receptor and initiates changes in cell 

               function, producing submaximal effect. 

        (c) Interacts with plasma protein amd doesn’t 

               produce any effect. 

        (d) Binds to receptor without directly altering their 

               function. 



     Answer ~ D



Q21: An competitive antagonists is a substance that:


        (a) Interact with receptor and produce submaximal effect. 

        (b) Binds to the same receptor site and progessively inhibits the agonists response. 

        (c) Binds to the non-specific sites of tissue. 

        (d) Binds to one receptor subtype as an agonist and to another as an antagonists. 



   Answer ~ B




Q22: The substance binding to one receptor subtype as an agonists and to another as an antagonists is :


        (a) Competitive antagonist

        (b) Irreversible antagonist

        (c) Agonist-antagonist

        (d) Partial agonist

        (e) Partial antagonist



    Answer ~ C




Q23: Which of the following substance whose mechanisms are based on interaction with ion channels :


        (a) Calcium channel blocker

        (b) Sodium channel blocker

        (c) Potassium channel activators

        (d) All of them



    Answer ~ D




Q24: Half life is the time required :


        (a) Metabolise a half of an introduced drug in plasma by half during elimination. 

        (b) Change the amount of drug in plasma by half during elimination. 

        (c) Absorb a half of an introduced drug. 

        (d) Binds half of an introduced drug to plasmaprotein. 



     Answer ~ B




Q25: Half life doesn’t depend upon :


        (a) Biotransformation

        (b) Time of drug absorption

        (c) Concentration of drug in plasma

        (d) Rate of drug elimination



     Answer ~ B




Q26: Elimination is expressed as follows : 


        (a) Rate of renal tubule reabsorption. 

        (b) Time required to decrease the amount of drug in plasma by one half. 

        (c) Clearance speed of some volume of blood from substance. 

        (d) Clearance of an organism from a xenobiotics. 



     Answer ~ D




Q27: Systemic ckearance is related with :

 

        (a) Only the concentration of substance in plasma. 

        (b) Only the elimination rate constant. 

        (c) Volume of distribution, half life, and elimination rate constant. 

        (d) Bioavailability & half life. 



      Answer ~ C




Q28: Acetaminophen undergoes which type of phase 1 reactions :


        (a) Deamination

        (b) S-oxidation

        (c) Amine oxidation

        (d) Dehydrogenation

        (e) Alkylation

  


     Answer ~ C




Q29: If 1mg if lorazepam produce the same anxiolytic response as 10mg of diazepine, which is correct?


        (a) Lorazepam is more potent than diazepine. 

        (b) Lorazepam is more effectious than diazepine. 

        (c) Lorazepam is full agonist and diazepam is the partial agonist. 

        (d) Lorazepam is a better drug to take for anxiety than is diazepam. 



       Answer ~ A




Q30: With IV infusion, a drug reaches 50% of it’s final steady state in 6 hours. The elimination half life of the drug must be approximately: 


        (a) 2h

        (b) 6h

        (c) 12h

        (d) 24h

        (e) 30h



   Answer ~ B






Labels:

Comments

Post a Comment

Popular posts from this blog

Autonomic Nervous System Anatomy and Physiology

           The Autonomic       Nervous System   • The Autonomic Nervous System(ANS) along with endocrine system coordinates  the regulation amd integeration of body functions.    •The ANS largerly independent (autonomous) in that its activities are not under direct conscious control. It is concenred primarily with visceral functions such as cardiac output, blood flow to various organs and digestions, which is necessary for life.    • Drugs that produce their primary therpeutic effect by mimicking or altering the functions of ANS are called autonomic drugs.    - The autonomic agents act either by stimulating portion of ANS or by blocking the action of autonomic nerves .    Nervous System overview :    • The N.S is divided into 2 anatomical divisions : The Central Nervous System which is composed of brain & spinal cord and the Peripheral Nervous System .    • Peripheral nervous system includes neurons which located outside the brain and spinal cord.    • The peripheral nervous syste
Post a Comment
Read more

AGONIST & ANTAGONIST with types

AGONIST       • Agonist is a chemical(drug) that binds to the receptor and activates the receptor to produce biological response.                                             OR       • Agonist is a drug that produce effects on endogenous compounds, when it interacts with it’s receptor.     => Agonists are of following types:      (1) Full agonists     (2) Partial agonists     (3) Inverse agonists (1) Full Agonists       • If a drug binds to a receptor and produce maximal biological response that mimics the response to endogenous ligand is called full agonist.   - All full agonists for a receptor population should produce the same E max. For Example : phenylephrine is a full agonist at alpha1-adrenoceptors, because it produce the same E max as the endogenous ligand, norepinephrine. Upon binding with aplha1-adrenoceptors on vascular smooth muscle, both phenylephrine and norepinephrine stablize the receptor in its active state, thereby increasing the Gq activation. Activation of Gq i
Read more

Mechanism of absorption of Drugs

    Absorption of Drugs • Absorption concerns the process of entry of drug in to systemic circulation from site of administration.  •The rate and extent of absorption depend on:   -the environment where the drug is absorbed   -chemical characteristics of drug   -route of administration (which influence bioavailability) • The route of administration other than intravenous may result in partial absorption and lower bioavailability.  (A) Mechanism of absorption of drug from GIT • Depending upon their chemical properties , drugs may be absorbed from GI tract by passive diffusion, facilitated diffusion, active transport or endocytosis.    (1) Passive diffusion :       • In this drug move from area of high concentration to area of lower concentration.                  - also known as non-ionic diffusion    - The driving force for this process is concentration or       electrochemical gradient.     - P.D does not require carrier, is not saturable, and shows low structural specifity.     - The
Post a Comment
Read more

Elimination of the Drug

          Drug Elimination   • Drugs must be sufficiently polar to be eliminated from the body.  • Removal of drugs from body occur via number of routes; the most important is elimination through kidney in to urine.  Renal Elimination of Drug • A drug passes through several process in the kidney before elimination, Glomerular filtration, tubular seceration , and passive tubular reabsorption.     (1) Glomerular filteration :   • Drugs enter the kidney through renal artries, which divide to form a glomerular capillary plexus. Free drug (not bound to albumin) flows through the capillary bed into bowman’s space as a part of glomerular filterate.    > Glomerular filteration rate is normally about 120mL/min. But may decrease sugnificantly in renal disease.       > pH and lipid solubility do not influence the passage of drugs into glomerular filterate.      > Variation in GFR and protein binding to drugs donot affect this process.    > water and polar compounds easily enter in gl
Post a Comment
Read more

Cholinergic neuron & Cholinergic Receptors

 •Drugs affecting the autonomic nervous system(ANS) are divided into two groups according to the type of neuron involved in mechanism of action.    •The cholinergic drugs, which act on receptors activated by acetylcholine(Ach), Where as adrenergic drugs act on receptors stimulated by epinephrine or norepinephrine.    •The cholinergic drugs act by either stimulating or blocking the receptors of the ANS.  The cholinergic neuron   • The preganglionic fibres terminating in adrenal medulla.    • The postganglionic fibres of parasympathetic division use ACh as a neurotransmitter.  The postganglionic sumpayhetic division of sweat glands also uses ACh.    • Ina ddition, cholinergicneurons innervate the muscles of somatic system and play an important role in CNS.  NEUROTRANSMISSION @ CHOLINERGIC NEURON :   • Neurotransmission at cholinergic neurons involves 6 sequential steps :   (1) Synthesis of ACh   (2) Storage of ACh    (3) Release of ACh   (4) Binding of ACh to the receptor   (5) Degradati
Post a Comment
Read more

Cholinergic Drugs (direct acting) Part-2

  (3) CARBACHOL (Carbamylcholine )   • Carbachol is is an ester of carbamic acid and poor substrate for AChEsterase. It is biotransformed by other esters at very slow rate.    • Carbachol has both Muscarinic and Nicotinic actions. Functions   (i) Actions :    • Carbachol has profound effects on both Cardiovascular system and GI system.    • It has ganglion stimulating activity and it may first stimulate and then depress these systems.    • It can cause release of epinephrine from adrenal medulla by its nicotinic functions.   On Eye :     • It cause miosis    • It cause spasm of accomodatiom in which the ciliary muscle of the eye remains in a constant state of contraction.    • Carbachol is also used to stimulate micturation by contraction of detrusor muscle. (ii) Therapeutic uses :     • Carbachol has high potency, receptor non-selectivity and relatively long duration of action.     • Carbachol is rarely used.     • Carbachol administered ocularly to induce miosis to reduce the intr
Post a Comment
Read more

PHARMACODYNAMICS & Drug Receptor Interaction

>Pharmacodynamics deals with the biochemical and physiological effect of drug as well as its mechanism of action.                                        OR We can simply define it as, The action of drug on the body.  •Most drug exert effects, both beneficial and harmful, by interacting with specialized target macromollecule called receptor.  Receptor : it refers to the drug binding site in the cell or on the surface of cell which mediate the action of drug.     • There are some drugs which do not require receptors Example = mannitol , anti-helmintic drugs, etc. NATURE OF DRUG RECEPTOR          1. Regulatory protein which mediates the action of endogenous chemical signals. For example : neurotransmitters , harmones and autocoids.           2. Enzymes. For example : dihydrofolic reductase          3. Transport protein. For example : sodium / potassium ATPase pump.           4. Structural protein. For example : tubulin.  RECEPTOR REGULATION      •Down Regulation : when receptors becom
Post a Comment
Read more

Cholinergic Drugs (Direct acting) Part-1

Cholinergic Agonists (direct acting)  • Cholinergic agonists mimic the effect of acetylcholine by binding directly to cholinoceptors (muscarinic & nicotinic).   • These agents are classified into 2 groups;     (1) Choline esters : it includes endogenous ACh and synthetic esters of choline. Such as Carbachol & Bethanechol .     (2) Naturally occuring Alkaloids : Nicotine & Pilocarpine .    • All direct-actings Cholinergic drugs have longer duration of action than Acetylcholine.    (1) ACETYLCHOLINE   • ACh is the quaternary ammonium compound that cannot penetrates membranes.    • It is nuerotransmitter of parasympathetic, somatic nerves & autonomic ganglia.    • It lacks the therapeutics importance b/c of multiple actions and its rapid inactivation by the cholinesterases.    • ACh has both muscarinic and nicotinic activity.    Functions :     (a) Decrease in heart rate and cardiac output :      • ACh mimics the effects of vagal stimulation on the heart.      • If in
Post a Comment
Read more

Drug clearance & Half Life & Dose

Drug Clearance It refers to the ratio of rate of drug elimination to the concentration of drug in biological fluid(C).                       CL = rate of elimination / C Rate of elimination   • For most of the drugs, elimination is not saturable & rate of drug elimination is directly proportional to concentration.                     Rate of elimination = CL x C ==> The difference between drug clearance and drug elimination is that :     • Clearance is Volume of blood cleared of drug per unit time and Elimination is amount of drug cleared from blood per unit time.  Total Body Clearance   • The total body systemic clearance , CLtotal is the sum of all clearances from drug metabolising and drug eliminating organs.                                         OR   • Dividing the rate of elimination at each organ by concentration of drug presented to it yeilds respective clearance at that organ and sum of these is total body clearance.                CLx = rate of elimination x / C      
Post a Comment
Read more

Drug Clearance by Biotranformation

Drug clearance : Once a drug enters into the body, the process of elimination begins. The three major routes of eliminations are: (i) Hepatic metabolism (ii) Biliary elimination (iii) Urinary excreation Excreation is irreversible removal of the drug from the body. It involves BIOTRANSFORMATION & EXCREATION.   •> Metabolism results in products with increase polarity, which allows the drug to be eliminated.  •> Clearance(CL) estimates the vomume of blood from which  the drug is cleared per unit of time.                            CL = 0.693 x V d / t  1/2    - W here T 1/2 is the elimination half life, Vd is apparent volume of distribution and 0.693 is natural log. BIOTRANSFORMATION               • The general principle of biotransformation is the metabolic conversion of drug mollecule to more water soluble metabolites that are more readily excreated.   - In many cases, metabolism of drug results in its conversion to compounds that have little or no pharmacological activity
Post a Comment
Read more