All of the following have 100% oral bioavailability EXCEPT
1.Valproic acid
2.Trimethoprim
3.Digoxin
4.Diazepam
Volume of distribution equals
1.Dose given/plasma concentration
2.Total amount of drug in the body/plasma concentration
3.Urine drug concentration/plasma concentration
4.Dose given/urine concentration
A D Response B C Concentration Which of these drugs is the most efficacious?
1.Drugs A and B
2.Drug C
3.Drugs A and D
4.Drugs D and C
A single compartment model means that
1.One exponential term describes the decreasing plasma concentration of the drug
2.A single exponential term describes the rise in plasma concentration following oral administration
3.The drug does not penetrate tissues
4.The drug is restricted to the ECF
Age associated changes in pharmacokinetics include
1.Reduction in creatinine clearance in 2/3 population
2. Decreased body fat
3.Increase body water
4.A greater reduction in conjugation compared with oxidation
All of the following drugs are >90% plasma protein bound EXCEPT
1.Diazepam
2.Frusemide
3.Fluoxetine
4.Gentamicin
All of the following drugs exhibit flow dependent elimination EXCEPT
1.Atenolol
2.Isoniazid
3.Propoxyphene
4.Amitriptylline
An example of drugs that undergo chemical antagonism is
1.Insulin - glucagon
2.Protamine - heparin
3.Prednisone - glipizide
4.Morphine - naloxone
Bioavailability is
1.The difference between the amount of drug absorbed and the amount excreted
2.The proportion of the drug in a formulation that is found in the systemic circulation
3.The AUC relating plasma concentration of drug to time after administration
4.Always identical with different formulations of the same drug
Clearance of which drug involves capacity limited elimination?
1.Theophylline
2.Gentamycin
3.Digoxin
4.Phenytoin
Drugs that enhance other drug metabolism include all of the following EXCEPT
1.Rifampicin
2.Ketoconazole
3.Phenobarbital
4.Griseofulvin
EC50 is
1.Always equal to Kd
2.Drug concentration with 50% receptors bound
3.Representation of the receptors affinity for drug binding
4. Drug concentration with 50% of maximal drug effect
First order kinetics
1.Means rate of reaction is proportional to concentration l
2.Are more common than zero order kinetics
3.Apply to exponential processes
4.Generally apply to high plasma concentrations (>20mg/100ml) of ethanol
Ligand gated channel receptors include all of the following EXCEPT
1.GABA
2.Aspartate
3.Glutamate
4.Ach-muscarinic
Referring to the graph in question 9 – which of the drugs is most potent?
1. A
2.B
3.C
4.D
Regarding biotransformation
1.Phase one reactions always precede phase two reactions
2.Skin is an organ involved in drug biotransformation
3.Water conjugation is a phase one reaction
4. CYP2D6 accounts for the majority of P450 activity
Regarding first order kinetics - all of the following are true EXCEPT
1.First order kinetics means rate of reaction is proportional to concentration
2.First order kinetics is more common than zero order kinetics
3.First order kinetics apply to exponential processes
4.First order kinetics generally apply to high plasma concentrations (>20 mg / 100 ml) of ethanol
Regarding pharmacology principles
1.Diffusion is directly proportional to thickness and inversely proportional to surface area
2.LD50 - 50% of the dose that kills most people
3. Efficacy is the maximum response produced by a drug
4.A partial agonist is always less potent than a full agonist
Regarding receptor regulation
1. Receptor down regulation occurs over hours – days
2.Receptor responses to drugs often “desensitise†with time – this desensitisation is usually irreversible
3.The mechanism of agonist induced desensitisation of the nicotinic Ach receptor has been worked out in detail
4.All “internalised†receptors are degraded by lysosomes
Reports of cardiac arrhythmias caused by unusually high blood levels of 2 antihistamines (terfenadine and astemizole) are best explained by
1.Concomitant treatment with phenobarbital
2.Use of these drugs by smokers
3.Use of antihistamines by persons of Asian background
4.Treatment of these patients with ketoconazole
The metabolic pathway of detoxification that become increasingly important in paracetamol toxicity is
1. Conjugation with glucuronide
2.Methylation
3.Reduction
4.Cytochrome p450 dependent glutathione conjugation
What is the half life of a drug with a volume of distribution of 100â„“/70kg and a clearance of 7â„“/hr/70kg
1.5 hours
2.10 hours
3.12.5 hours
4.15 hours
What is the half life of a drug with a volume of distribution of 700l/70kg and clearance of 49l/hour/70kg?
1.What is the half life of a drug with a volume of distribution of 700l/70kg and clearance of 49l/hour/70kg? A. 5 hours
2.7 hours
3.10 hours
4.12.5 hours
Which of the following acts on intracellular receptors
1.Serotonin
2.Glucagon
3.Corticosteroids
4.GABA
Which of the following drugs has a high extraction ratio?
1.Diazepam
2.Theophylline
3.Phenytoin
4.Propranolol
Which of the following drugs has a volume of distribution >2000 â„“/70kg?
1.Aspirin
2.Digoxin
3.Propranolol
4.Chloroquine
Which of the following drugs has an average half life of 50 hours?
1. Nortriptylline
2.Digoxin
3.Trimethoprim
4.Valproic acid
Which of the following drugs undergoes rate limited elimination?
1.Lignocaine
2.Morphine
3.Propanolol
4.Aspirin
Which of the following has ↑ bioavailability in the neonate whencompared with older children/adults?
1.Penicillin
2.Digoxin
3.Acetaminophen
4.Diazepam
Which of the following has ↑ bioavailability in the neonate whencompared with older children/adults?
1.Penicillin
2.Digoxin
3.Acetaminophen
4.Diazepam
Which of the following has the largest volume of distribution?
1.Digoxin
2.Imipramine
3.Lithium
4.Chloroquine
Which of the following has the shortest half life?
1.Theophylline
2.Diazepam
3.Aspirin
4.Lithium
Which of the following is >90% bound to plasma proteins?
1.Atenolol
2.Diazepam
3.Gentamycin
4.Lithium
Which of the following is a phase one reaction?
1.Reduction
2.Acetylation
3.Glucuronidation
4.Methylation
Which of the following receptor - ligand pathway is correct?
1.Insulin - G protein receptor
2.Mineralocorticoid - tyrosine kinase receptor
3. Vitamin D - intracellular receptor
4.Adrenaline - ligand gated channel receptor
Which of the following statements is correct?Diazepam has a high extraction ratio and is thus subject to flow dependent elimination
1. The half life is the time taken for a parameter to fall to 1/4 its original value
2. Partial agonists act at receptor sites to cause maximal pharmacological effect at high doses
3.Diazepam has a high extraction ratio and is thus subject to flow dependent elimination
4.A patient with oedema will have an increased volume of distribution of tobramycin
Which of the following undergoes a phase I hydrolysis reaction?(biotransformation)
1.Ethanol
2.Naloxone
3.Morphine
4.Lignocaine
Which of the following undergoes acetylation in the liver? (Phase 2 biotransformation)
1.Isoniazid
2.Acetaminophen
3.Salicylic acid
4.Epinephrine
Which of the following will NOT alter the volume of distribution of a drug?
1.Cardiac failure
2.Clearance
3.Age
4.Burns
You are given a vial with 15 ml of 0.5% prilocaine to do an arm block. How many mg of prilocaine are you injecting?
1. 15 mg
2.30 mg
3.50 mg
4.75 mg