Regarding fluoroquinolones

Ciprofloxacin is ineffective in the treatment of gonococcus

Norfloxacin and Ciprofloxacin are predominantly faecally excreted

Norfloxacin and Ciprofloxacin have long half lives (12 hours)

They have poor oral bioavailability

May damage growing cartilage in children less than 18 years of age

Have enhanced activity at acidic pH

Have little activity against legionella

Have half lives which increase in patients with anuria

Are contraindicated in neonates

Can cause discoloration of developing teeth when given to children

Does not penetrate the blood brain barrier

Must be administered parenterally

Can be safely used in premature infants

Can cause depression of bone marrow function

Can cause discoloration of developing teeth when given to children

Is ineffective against streptococci

Is active against enterococci and anaerobes

Blocks transpeptidation and inhibits peptidoglycan synthesis

Has excellent penetration into CNS and prostate

Is never orally administered as it is poorly absorbed from the GIT

Binds to the 30S unit on the ribosome and inhibits protein synthesis

60% of vancomycin is excreted by glomerular filtration

Parenteral vancomycin is commonly used for treatment of infections caused by methicillin susceptible staphylococci

Adverse reactions to vancomycin are encountered in about 10% of patients

Work by inhibiting dihydrofolate reductase

May be administered to patients with severe campylobacter infection

Work by inhibiting dihydrofolate reductase

Have little effect against gram positive organisms

Are heavily metabolised in the liver

Are safe to give to breast feeding mothers

Penetrates through BBB into CSF well

Inhibits bacterial cell wall synthesis

Is often used for prophylaxis of endocarditis in patients with Valvular disease who are undergoing dental procedures

Penetrates through BBB into CSF well

Works well against enterococci and gram negative aerobic organisms

Regarding paraquat poisoning

Oxygen high flow stops the pulmonary lesions occurring

The interval between ingestion and death is usually hours because of immediate pulmonary toxicity

Mechanism of action involves single electron oxidation of the herbicide to free radical species

Probable human lethal dosage is 50-500mg/kg

Oxygen high flow stops the pulmonary lesions occurring

Paraquat doesn t affect hepatic or renal functions

Regarding paracetamol (acetaminophen)

Less than 5% is excreted unchanged

Acetaminophen has no anti-inflammatory properties

The half life of paracetamol is 2-3 hours

Haemolytic anaemia has rarely been noted with paracetamol

Regarding lead toxicity

High dose organic lead poisoning usually results in severe pneumonitis

Lead can induce an anaemia that is macrocytic

Young children absorb about 10% of ingested inorganic lead

Lead induced peripheral neuropathy often involves upper limb extensors resulting in wrist drop

High dose organic lead poisoning usually results in severe pneumonitis

All patients with elevated blood lead levels should have chelation treatment whether symptomatic or not

Regarding agents used to treat gout

Allopurinol is a xanthine oxidase stimulator

As little as 8mg of colchicine taken over 24 hours may be fatal

Allopurinol is a xanthine oxidase stimulator

Probenecid is an organic alkaline substance

Colchicine may precipitate acute attacks of gout

Aspirin is effective against gout as it inhibits urate crystal phagocytosis

The main mechanism of action of colchicine is

Inhibition of synoviocyte phagocytosis

Inhibition of polymorphonuclear leucocytes

Inhibition of synoviocyte phagocytosis

Reduced formation of leukotriene D4

Inhibition of mononuclear phagocytes

Decreasing the body pool of urate

At low toxic doses respiratory acidosis may occur

The average anti-inflammatory dose of aspirin is 0.6g up to 4 hourly

Aspirin s main side effect at usual doses is rash

Aspirin s antiplatelet effect lasts 8 10 days

At low toxic doses respiratory acidosis may occur

All of the following are recognised adverse effects of isoniazid EXCEPT

Phenytoin metabolism Phenytoin blood levels and toxicity

Preferentially binds to activated state sodium channels

Is the drug treatment of choice in absence seizures

Undergoes flow limited elimination

Steady state mean plasma concentrations varies disproportionately with the dose

Preferentially binds to activated state sodium channels

Has a half life of around 10 hours

Predictably reverses benzodiazepine induced respiratory depression

Antagonises CNS effects of opioids

Can precipitate seizures in mixed overdose

Has a half life of around 10 hours

The most frequent neurological abnormality in chronic alcoholism is asymmetrical peripheral nerve injury specific to hands and feet

Is metabolised by the MEOS system at blood concentrations below 100mg/dl

The most frequent neurological abnormality in chronic alcoholism is asymmetrical peripheral nerve injury specific to hands and feet

Alcohol is estimated to be responsible for approximately 10% of cases of hypertension

Regarding the antiepileptic drugs

Vigabatrin works by sodium channel blockade

Lorazepam has documented efficacy against absence seizures

Phenytoin is able to stimulate its own metabolism by enzyme induction

Valproate has a large Vd (>500l/70kg)

The most common dose related adverse effects of Carbamazepine are ataxia and diplopia

Vigabatrin works by sodium channel blockade

Increase the duration of GABA gated chloride channel openings

Will depress (in high doses) the CNS to the point known as stage 3 of general anaesthesia

Have extensive cardiodepressant effects in doses used to cause hypnosis

Decrease the duration of stage 2 NREM sleep

All of the following are recognized adverse effects of isoniazid EXCEPT

Decreased phenytoin metabolism increased phenytoin blood levels / toxicity

Regarding drugs used in Parkinson s disease

Anti muscarinic drugs are of benefit in elimination of bradykinesia in Parkinson s

Bromocriptine is the first line drug to treat Parkinson s disease in psychotic patients

80-90% of a single dose of Levodopa enters the brain unaltered

Patients taking Selesiline to treat Parkinson s disease are limited in what they can eat because of the tyranine reaction phenomenon

Amantadine has anti Parkinsonian effects and is administered at a dose of 100mg bd

Anti muscarinic drugs are of benefit in elimination of bradykinesia in Parkinson s

With respect to opioid receptors

Methadone is used for heroin withdrawal because its actions are predominantly at the delta receptors

Fentanyl works predominantly at the kappa receptors

Both U and delta receptors contribute to respiratory depression

Methadone is used for heroin withdrawal because its actions are predominantly at the delta receptors

Opioid receptors are coupled to a tyrosine kinase mechanism of action

Physical dependence and tolerance is caused by the rapid disintegration of receptors

Penetrates the axon in its changed form

Is more potent than bupivacaine

Has higher affinity for activated than resting sodium channels

Blocks voltage gated sodium channels at their extracellular end

Regarding adverse effects of propofol

Severe acidosis can occur with its use in paediatric respiratory infections

Can be used IM or IV to induce anaesthesia

Anaesthetic action is terminated by redistribution from CNS to other highly vascularised tissues

Is used to treat nausea caused by morphine

Is not appreciably protein bound

Inhibits hepatic microsomal enzymes

Is bactericidal for mycobacteria

Is not appreciably protein bound

Is predominantly excreted unchanged in the urine

Can produce neuromuscular blockade

Normally reach high CSF concentrations

Have good oral absorption but high first pass metabolism

Is a defluorinated analogue of nalidixic acid

Inhibits tropoisomerases 2 and 3

Its action is directly terminated by the action of plasma cholinesterase

Is a non-depolarising neuromuscular blocking agent

Is contraindicated in all eye operations

Stimulates cardiac muscarinic receptors and autonomic ganglia

Its action is directly terminated by the action of plasma cholinesterase

Should not be administered to patients with burns >24 hours old because of its hypercalcaemic effect

Delvindine is a nucleoside reverse transcriptase inhibitor (NRTI)

Zidovudine (AZT) is a non nucleoside reverse transcriptase inhibitor (NNRTI)

NRTIs activate HIV-1 reverse transcriptase

Abacavir is a protease inhibitor

NRTIs require intracytoplasmic activation to the triphosphate form

Is mostly conjugated by the liver and excreted in the bile

Is hydrolysed to acetone and salicylate

Exhibits first order kinetics with elimination in low doses

Is mostly conjugated by the liver and excreted in the bile

Reversibly blocks the cyclooxygenase enzyme

Causes an immediate doubling of bleeding time

Use of ibuprofen and aspirin together increases the anti inflammatory effect

At high doses diclofenac demonstrates zero order kinetics

Aspirin is a reversible inhibitor of cyclooxygenase

All NSAIDs can be found in synovial fluid after repeated dosing

Use of ibuprofen and aspirin together increases the anti inflammatory effect

The metabolic pathway of detoxification that becomes increasingly important in paracetamol toxicity is

Cytochrome p-450 dependent glutathione conjugation

Which of the following antidote drug pairings is INCORRECT

Acetaminophen n-acetyl cysteine

Tricyclic antidepressants physostigmine

Regarding carbon monoxide poisoning

With room air at 1atm the elimination half time of CO is about 80 minutes

CO has an affinity for Hb that is about 2000 times that of oxygen

Hyperbaric oxygen is indicated as a treatment for all patients with CO Hb levels >20%

The average concentration of CO in the atmosphere is about 0.1ppm

With room air at 1atm the elimination half time of CO is about 80 minutes

The foetus is resistant to the effects of CO exposure

137 + Mcqs in Pharmacology in Biology Page 1 McqOptions

1.	Regarding fluoroquinolones
A.	Ciprofloxacin is ineffective in the treatment of gonococcus
B.	Norfloxacin and Ciprofloxacin are predominantly faecally excreted
C.	Norfloxacin and Ciprofloxacin have long half lives (12 hours)
D.	They have poor oral bioavailability
E.	May damage growing cartilage in children less than 18 years of age
Answer» F.

Discussion

2.	Macrolides
A.	Have enhanced activity at acidic pH
B.	Have little activity against legionella
C.	Have half lives which increase in patients with anuria
D.	Induce cytochrome p450 enzymes
E.	Are contraindicated in neonates
Answer» D. Induce cytochrome p450 enzymes

Discussion

3.	Chloramphenicol
A.	Does not penetrate the blood brain barrier
B.	Must be administered parenterally
C.	Can be safely used in premature infants
D.	Can cause depression of bone marrow function
E.	Can cause discoloration of developing teeth when given to children
Answer» E. Can cause discoloration of developing teeth when given to children

Discussion

4.	Flucloxacillin
A.	Is ineffective against streptococci
B.	Is active against enterococci and anaerobes
C.	Blocks transpeptidation and inhibits peptidoglycan synthesis
D.	Is poorly absorbed orally
E.	Has excellent penetration into CNS and prostate
Answer» D. Is poorly absorbed orally

Discussion

5.	Spironolactone
A.	Has a steroid structure
B.	Is a partial agonist
C.	Promotes sodium retention
D.	Increases potassium loss
E.	Is a loop diuretic
Answer» B. Is a partial agonist

Discussion

6.	Vancomycin
A.	Is never orally administered as it is poorly absorbed from the GIT
B.	Binds to the 30S unit on the ribosome and inhibits protein synthesis
C.	60% of vancomycin is excreted by glomerular filtration
D.	Parenteral vancomycin is commonly used for treatment of infections caused by methicillin susceptible staphylococci
E.	Adverse reactions to vancomycin are encountered in about 10% of patients
Answer» F.

Discussion

7.	The fluoroquinolones
A.	May be administered to patients with severe campylobacter infection
B.	Work by inhibiting dihydrofolate reductase
C.	Have little effect against gram positive organisms
D.	Are heavily metabolised in the liver
E.	Are safe to give to breast feeding mothers
Answer» B. Work by inhibiting dihydrofolate reductase

Discussion

8.	Clindamycin
A.	Inhibits bacterial cell wall synthesis
B.	Is often used for prophylaxis of endocarditis in patients with Valvular disease who are undergoing dental procedures
C.	Penetrates through BBB into CSF well
D.	Works well against enterococci and gram negative aerobic organisms
E.	Is 10% protein bound
Answer» C. Penetrates through BBB into CSF well

Discussion

9.	Aspirin inhibits all of the following EXCEPT
A.	Cyclo oxygenase
B.	Recurrent miscarriages
C.	Protacyclin synthesis
D.	Kallikrein system
E.	Lipo oxygenase
Answer» F.

Discussion

10.	Regarding paraquat poisoning
A.	The interval between ingestion and death is usually hours because of immediate pulmonary toxicity
B.	Mechanism of action involves single electron oxidation of the herbicide to free radical species
C.	Probable human lethal dosage is 50-500mg/kg
D.	Oxygen high flow stops the pulmonary lesions occurring
E.	Paraquat doesn t affect hepatic or renal functions
Answer» D. Oxygen high flow stops the pulmonary lesions occurring

Discussion

11.	Regarding paracetamol (acetaminophen)
A.	Less than 5% is excreted unchanged
B.	Acetaminophen has no anti-inflammatory properties
C.	The half life of paracetamol is 2-3 hours
D.	Haemolytic anaemia has rarely been noted with paracetamol
E.	All of the above are true
Answer» F.

Discussion

12.	Regarding lead toxicity
A.	Lead can induce an anaemia that is macrocytic
B.	Young children absorb about 10% of ingested inorganic lead
C.	Lead induced peripheral neuropathy often involves upper limb extensors resulting in wrist drop
D.	High dose organic lead poisoning usually results in severe pneumonitis
E.	All patients with elevated blood lead levels should have chelation treatment whether symptomatic or not
Answer» D. High dose organic lead poisoning usually results in severe pneumonitis

Discussion

13.	Regarding agents used to treat gout
A.	As little as 8mg of colchicine taken over 24 hours may be fatal
B.	Allopurinol is a xanthine oxidase stimulator
C.	Probenecid is an organic alkaline substance
D.	Colchicine may precipitate acute attacks of gout
E.	Aspirin is effective against gout as it inhibits urate crystal phagocytosis
Answer» B. Allopurinol is a xanthine oxidase stimulator

Discussion

14.	The main mechanism of action of colchicine is
A.	Inhibition of polymorphonuclear leucocytes
B.	Inhibition of synoviocyte phagocytosis
C.	Reduced formation of leukotriene D4
D.	Inhibition of mononuclear phagocytes
E.	Decreasing the body pool of urate
Answer» B. Inhibition of synoviocyte phagocytosis

Discussion

15.	All of the following may be seen in organophosphate poisoning EXCEPT
A.	Salivation
B.	Tachycardia
C.	Fibrillation of muscle fibres
D.	Bronchospasm
E.	Vomiting
Answer» C. Fibrillation of muscle fibres

Discussion

16.	Regarding aspirin
A.	The average anti-inflammatory dose of aspirin is 0.6g up to 4 hourly
B.	Aspirin s main side effect at usual doses is rash
C.	Aspirin s antiplatelet effect lasts 8 10 days
D.	At low toxic doses respiratory acidosis may occur
E.	Aspirin has a pka of 4.5
Answer» D. At low toxic doses respiratory acidosis may occur

Discussion

17.	Which of the following is a direct serotonin agonist
A.	Fluoxetine
B.	Amitriptylline
C.	Moclobemide
D.	Ondansetron
E.	Sumatriptan
Answer» F.

Discussion

18.	All of the following are recognised adverse effects of isoniazid EXCEPT
A.	Hepatitis
B.	Peripheral neuropathy
C.	Retrobulbar neuritis
D.	Phenytoin metabolism Phenytoin blood levels and toxicity
E.	CNS toxicity
Answer» D. Phenytoin metabolism Phenytoin blood levels and toxicity

Discussion

19.	Phenytoin
A.	Is 20-30% bound to albumin
B.	Is the drug treatment of choice in absence seizures
C.	Undergoes flow limited elimination
D.	Steady state mean plasma concentrations varies disproportionately with the dose
E.	Preferentially binds to activated state sodium channels
Answer» E. Preferentially binds to activated state sodium channels

Discussion

20.	Flumazenil
A.	Is cleared renally
B.	Predictably reverses benzodiazepine induced respiratory depression
C.	Antagonises CNS effects of opioids
D.	Can precipitate seizures in mixed overdose
E.	Has a half life of around 10 hours
Answer» E. Has a half life of around 10 hours

Discussion

21.	The opiate associated with seizures when given in high doses to patients with renal failure is
A.	Morphine
B.	Pethidine
C.	Methadone
D.	Fentanyl
E.	Codeine
Answer» C. Methadone

Discussion

22.	Ethanol
A.	Is lipid soluble
B.	Is metabolised by the MEOS system at blood concentrations below 100mg/dl
C.	Is a vasodilator
D.	The most frequent neurological abnormality in chronic alcoholism is asymmetrical peripheral nerve injury specific to hands and feet
E.	Alcohol is estimated to be responsible for approximately 10% of cases of hypertension
Answer» D. The most frequent neurological abnormality in chronic alcoholism is asymmetrical peripheral nerve injury specific to hands and feet

Discussion

23.	Regarding the antiepileptic drugs
A.	Lorazepam has documented efficacy against absence seizures
B.	Phenytoin is able to stimulate its own metabolism by enzyme induction
C.	Valproate has a large Vd (>500l/70kg)
D.	The most common dose related adverse effects of Carbamazepine are ataxia and diplopia
E.	Vigabatrin works by sodium channel blockade
Answer» E. Vigabatrin works by sodium channel blockade

Discussion

24.	Benzodiazepines
A.	Increase the duration of GABA gated chloride channel openings
B.	Will depress (in high doses) the CNS to the point known as stage 3 of general anaesthesia
C.	Bind to GABA receptors
D.	Have extensive cardiodepressant effects in doses used to cause hypnosis
E.	Decrease the duration of stage 2 NREM sleep
Answer» C. Bind to GABA receptors

Discussion

25.	All of the following are recognized adverse effects of isoniazid EXCEPT
A.	Hepatitis
B.	Peripheral neuropathy
C.	Retrobulbar neuritis
D.	Decreased phenytoin metabolism increased phenytoin blood levels / toxicity
E.	CNS toxicity
Answer» D. Decreased phenytoin metabolism increased phenytoin blood levels / toxicity

Discussion

26.	Regarding drugs used in Parkinson s disease
A.	Bromocriptine is the first line drug to treat Parkinson s disease in psychotic patients
B.	80-90% of a single dose of Levodopa enters the brain unaltered
C.	Patients taking Selesiline to treat Parkinson s disease are limited in what they can eat because of the tyranine reaction phenomenon
D.	Amantadine has anti Parkinsonian effects and is administered at a dose of 100mg bd
E.	Anti muscarinic drugs are of benefit in elimination of bradykinesia in Parkinson s
Answer» E. Anti muscarinic drugs are of benefit in elimination of bradykinesia in Parkinson s

Discussion

27.	With respect to opioid receptors
A.	Fentanyl works predominantly at the kappa receptors
B.	Both U and delta receptors contribute to respiratory depression
C.	Methadone is used for heroin withdrawal because its actions are predominantly at the delta receptors
D.	Opioid receptors are coupled to a tyrosine kinase mechanism of action
E.	Physical dependence and tolerance is caused by the rapid disintegration of receptors
Answer» C. Methadone is used for heroin withdrawal because its actions are predominantly at the delta receptors

Discussion

28.	Lignocaine
A.	Penetrates the axon in its changed form
B.	Is more potent than bupivacaine
C.	Has higher affinity for activated than resting sodium channels
D.	Is a weak acid
E.	Blocks voltage gated sodium channels at their extracellular end
Answer» D. Is a weak acid

Discussion

29.	Regarding adverse effects of propofol
A.	Post op vomiting is common
B.	Hypertension is a complication
C.	Severe acidosis can occur with its use in paediatric respiratory infections
D.	It is positively inotropic
E.	Tremor is a common side effect
Answer» D. It is positively inotropic

Discussion

30.	Thiopentone
A.	Is not lipid soluble
B.	Can be used IM or IV to induce anaesthesia
C.	Has good analgesic properties
D.	Can cause convulsive movements
E.	Anaesthetic action is terminated by redistribution from CNS to other highly vascularised tissues
Answer» F.

Discussion

31.	The main side effect of benztropine is
A.	Miosis
B.	Confusion
C.	Diarrhoea
D.	GIT haemorrhage
E.	Bronchorrhoea
Answer» C. Diarrhoea

Discussion

32.	Codeine
A.	Is more potent than fentanyl
B.	Frequently causes diarrhoea
C.	Is used to treat nausea caused by morphine
D.	Occurs in foxglove plants
E.	Depresses the cough reflex
Answer» F.

Discussion

33.	Which of the following symptoms of aspirin toxicity occurs at plasma salicylate concentrations of 100mg/dl?
A.	Tinnitus
B.	Vasomotor collapse
C.	Metabolic acidosis
D.	Gastric intolerance
E.	Renal failure
Answer» D. Gastric intolerance

Discussion

34.	Which of the following is considered to be bacteriostatic?
A.	Penicillin
B.	Chloramphenicol
C.	Ciprofloxacin
D.	Cefoxitin
E.	Tobramycin
Answer» C. Ciprofloxacin

Discussion

35.	Rifampicin
A.	Inhibits hepatic microsomal enzymes
B.	Inhibits DNA synthesis
C.	Is bactericidal for mycobacteria
D.	Is not appreciably protein bound
E.	Is predominantly excreted unchanged in the urine
Answer» D. Is not appreciably protein bound

Discussion

36.	All of the following inhibit nucleic acid synthesis EXCEPT
A.	Norfloxacillin
B.	Chloramphenicol
C.	Trimethoprim
D.	Rifampicin
E.	Sulfasalazine
Answer» C. Trimethoprim

Discussion

37.	Which of the following inhibits DNA gyrase?
A.	Penicillin
B.	Trimethoprim
C.	Chloramphenicol
D.	Ciprofloxacin
E.	Gentamicin
Answer» E. Gentamicin

Discussion

38.	Aminoglycosides
A.	Have a lactam ring
B.	Can produce neuromuscular blockade
C.	Are DNA gyrase inhibitors
D.	Normally reach high CSF concentrations
E.	Have good oral absorption but high first pass metabolism
Answer» C. Are DNA gyrase inhibitors

Discussion

39.	Ciprofloxacin
A.	Is a defluorinated analogue of nalidixic acid
B.	Inhibits tropoisomerases 2 and 3
C.	Has no gram positive cover
D.	Has bioavailability of 30%
E.	May cause an arthropathy
Answer» E. May cause an arthropathy

Discussion

40.	Acetaminophen (paracetamol) can undergo all of the following biotransformation reactions EXCEPT
A.	Deamination
B.	N-oxidation
C.	Glucuronidation
D.	Sulphation
E.	Glutathione conjugation
Answer» B. N-oxidation

Discussion

41.	Suxamethonium
A.	Is a non-depolarising neuromuscular blocking agent
B.	Is contraindicated in all eye operations
C.	Stimulates cardiac muscarinic receptors and autonomic ganglia
D.	Its action is directly terminated by the action of plasma cholinesterase
E.	Should not be administered to patients with burns >24 hours old because of its hypercalcaemic effect
Answer» D. Its action is directly terminated by the action of plasma cholinesterase

Discussion

42.	Regarding antivirals
A.	Delvindine is a nucleoside reverse transcriptase inhibitor (NRTI)
B.	Zidovudine (AZT) is a non nucleoside reverse transcriptase inhibitor (NNRTI)
C.	NRTIs activate HIV-1 reverse transcriptase
D.	Abacavir is a protease inhibitor
E.	NRTIs require intracytoplasmic activation to the triphosphate form
Answer» F.

Discussion

43.	Aspirin
A.	Is hydrolysed to acetone and salicylate
B.	Exhibits first order kinetics with elimination in low doses
C.	Is mostly conjugated by the liver and excreted in the bile
D.	Reversibly blocks the cyclooxygenase enzyme
E.	Causes an immediate doubling of bleeding time
Answer» C. Is mostly conjugated by the liver and excreted in the bile

Discussion

44.	Regarding NSAIDs
A.	At high doses diclofenac demonstrates zero order kinetics
B.	Aspirin is a reversible inhibitor of cyclooxygenase
C.	Aspirin at doses of <2g/day reduces uric acid levels
D.	All NSAIDs can be found in synovial fluid after repeated dosing
E.	Use of ibuprofen and aspirin together increases the anti inflammatory effect
Answer» E. Use of ibuprofen and aspirin together increases the anti inflammatory effect

Discussion

45.	The metabolic pathway of detoxification that becomes increasingly important in paracetamol toxicity is
A.	Conjugation with glucuronide
B.	Oxidation
C.	Reduction
D.	Cytochrome p-450 dependent glutathione conjugation
E.	Methylation
Answer» E. Methylation

Discussion

46.	Which of the following NSAIDs has a t1/2 of about 1 hour
A.	Diclofenac
B.	Naproxen
C.	Piroxicam
D.	Indomethacin
E.	Ibuprofen
Answer» B. Naproxen

Discussion

47.	Which of the following drug overdoses may be amenable to the elimination technique of haemodialysis
A.	Calcium channel blockers
B.	Benzodiazepines
C.	Valproate
D.	Quinidine
E.	Opioids
Answer» D. Quinidine

Discussion

48.	Which of the following antidote drug pairings is INCORRECT
A.	Acetaminophen n-acetyl cysteine
B.	blockers glucagon
C.	Opioids naloxone
D.	Benzodiazepines Flumazenil
E.	Tricyclic antidepressants physostigmine
Answer» F.

Discussion

49.	Regarding carbon monoxide poisoning
A.	CO has an affinity for Hb that is about 2000 times that of oxygen
B.	Hyperbaric oxygen is indicated as a treatment for all patients with CO Hb levels >20%
C.	The average concentration of CO in the atmosphere is about 0.1ppm
D.	With room air at 1atm the elimination half time of CO is about 80 minutes
E.	The foetus is resistant to the effects of CO exposure
Answer» D. With room air at 1atm the elimination half time of CO is about 80 minutes

Discussion

50.	All of the following drugs can cause a wide anion gap metabolic acidosis EXCEPT
A.	Lithium
B.	Methanol
C.	Cyanide
D.	Salicylates
E.	Isoniazid
Answer» B. Methanol

Discussion

Explore topic-wise MCQs in Biology.

Regarding fluoroquinolones

Macrolides

Chloramphenicol

Flucloxacillin

Spironolactone

Vancomycin

The fluoroquinolones

Clindamycin

Aspirin inhibits all of the following EXCEPT

Regarding paraquat poisoning

Regarding paracetamol (acetaminophen)

Regarding lead toxicity

Regarding agents used to treat gout

The main mechanism of action of colchicine is

All of the following may be seen in organophosphate poisoning EXCEPT

Regarding aspirin

Which of the following is a direct serotonin agonist

All of the following are recognised adverse effects of isoniazid EXCEPT

Phenytoin

Flumazenil

The opiate associated with seizures when given in high doses to patients with renal failure is

Ethanol

Regarding the antiepileptic drugs

Benzodiazepines

All of the following are recognized adverse effects of isoniazid EXCEPT

Regarding drugs used in Parkinson s disease

With respect to opioid receptors

Lignocaine

Regarding adverse effects of propofol

Thiopentone

The main side effect of benztropine is

Codeine

Which of the following symptoms of aspirin toxicity occurs at plasma salicylate concentrations of 100mg/dl?

Which of the following is considered to be bacteriostatic?

Rifampicin

All of the following inhibit nucleic acid synthesis EXCEPT

Which of the following inhibits DNA gyrase?

Aminoglycosides

Ciprofloxacin

Acetaminophen (paracetamol) can undergo all of the following biotransformation reactions EXCEPT

Suxamethonium

Regarding antivirals

Aspirin

Regarding NSAIDs

The metabolic pathway of detoxification that becomes increasingly important in paracetamol toxicity is

Which of the following NSAIDs has a t1/2 of about 1 hour

Which of the following drug overdoses may be amenable to the elimination technique of haemodialysis

Which of the following antidote drug pairings is INCORRECT

Regarding carbon monoxide poisoning

All of the following drugs can cause a wide anion gap metabolic acidosis EXCEPT