Drugs which enhance other drug metabolism include all of the following EXCEPT
1.Rifampicin
2.Ketoconazole
3.Phenobarbital
4.Griseofulvin
Regarding fluoroquinolones
1.Ciprofloxacin is ineffective in the treatment of gonococcus
2.Norfloxacin and Ciprofloxacin are predominantly faecally excreted
3.They have poor oral bioavailability
4.May damage growing cartilage in children less than 18 years of age
Regarding lead toxicity
1.Lead can induce an anaemia that is macrocytic
2.Young children absorb about 10% of ingested inorganic lead
3. Lead induced peripheral neuropathy often involves upper limb extensors resulting in wrist drop
4.All patients with elevated blood lead levels should have chelation treatment whether symptomatic or not
Regarding paraquat poisoning
1.The interval between ingestion and death is usually hours because of immediate pulmonary toxicity
2. Mechanism of action involves single electron oxidation of the herbicide to free radical species
3.Probable human lethal dosage is 50-500mg/kg
4. Oxygen high flow stops the pulmonary lesions occurring
The fluoroquinolones
1. May be administered to patients with severe campylobacter infection
2.Work by inhibiting dihydrofolate reductase
3.Have little effect against gram positive organisms
4.Are heavily metabolised in the liver
Vancomycin
1.90% of vancomycin is excreted by glomerular filtration
2. Inhibits proteinsynthesis in bacteria
3.Is bactericidal against gram negative bacilli
4.Is well absorbed from the GIT
Which of the following is a second generation cephalosporin?
1.Cefaclor
2.Ceftazidime
3.Cephalexin
4.Cefotaxime
Acetaminophen (paracetamol) can undergo all of the following biotransformation reactions EXCEPT
1.Deamination
2.N-oxidation
3.Glucuronidation
4.Sulphation
All of the following antibiotics bind to the 50S subunit of the ribosome thereby inhibitingproteinsynthesis EXCEPT
1.Chloramphenicol
2.Erythromycin
3.Linezolid
4.Doxycycline
All of the following are NSAIDs EXCEPT
1.Sulindac
2.Piroxicam
3.Gemfibrozil
4.Ketorolac
All of the following are recognised adverse effects of isoniazid EXCEPT
1.Hepatitis
2.Peripheral neuropathy
3.Retrobulbar neuritis
4. ↓ Phenytoin metabolism → ↑ Phenytoin blood levels and toxicity
All of the following are recognized adverse effects of isoniazid EXCEPT
1.Hepatitis
2.Peripheral neuropathy
3.Retrobulbar neuritis
4.Decreased phenytoin metabolism – increased phenytoin blood levels / toxicity
All of the following are true regarding penicillins EXCEPT
1.Most penicillins only cross the blood brain barrier when the meninges are inflamed.
2. Penicillins don’t require dosage adjustment in renal failure
3.Penicillins inhibit cross linkage of peptidoglycans in the cell wall
4.Piperacillin is a penicillin active against pseudomonas
All of the following drugs can cause a wide anion gap metabolic acidosis EXCEPT
1. Lithium
2.Methanol
3.Cyanide
4.Salicylates
All of the following inhibit nucleic acid synthesis EXCEPT
1.Norfloxacillin
2.Chloramphenicol
3.Trimethoprim
4.Rifampicin
All of the following may be seen in organophosphate poisoning EXCEPT
1.Salivation
2.Tachycardia
3.Fibrillation of muscle fibres
4.Bronchospasm
Aspirin
1.Is hydrolysed to acetone and salicylate
2. Exhibits first order kinetics with elimination in low doses
3.Is mostly conjugated by the liver and excreted in the bile
4.Reversibly blocks the cyclooxygenase enzyme
Aspirin inhibits all of the following EXCEPT
1.Cyclo oxygenase
2.Recurrent miscarriages
3.Protacyclin synthesis
4.Lipo oxygenase
Chloramphenicol
1. Does not penetrate the blood brain barrier
2. Must be administered parenterally
3.Can be safely used in premature infants
4.Can cause depression of bone marrow function
Ciprofloxacin
1.Inhibits tropoisomerases 2 and 3
2.Has a bioavailability of 30%
3. Has no gram positive cover
4.May cause an arthropathy
Clindamycin
1.Inhibits bacterial cell wall synthesis
2.Is often used for prophylaxis of endocarditis in patients with Valvular disease who are undergoing dental procedures
3.Penetrates through BBB into CSF well
4.Works well against enterococci and gram negative aerobic organisms
Erethism†is seen in which of the following intoxications
1. Lead
2.Mercury
3.Arsine gas
4.Penicillamine
Flucloxacillin
1.Is ineffective against streptococci
2. Is active against enterococci and anaerobes
3.Blocks transpeptidation and inhibits peptidoglycan synthesis
4.Is poorly absorbed orally
Heparin and protamine used together is an example of
1.Physiologic antagonism
2.Chemical antagonism
3.Partial agonism
4.Irreversible antagonism
Macrolides
1.Have enhanced activity at acidic pH
2.Have little activity against legionella
3.Have half lives which increase in patients with anuria
4.Are contraindicated in neonates
Pharmacokinetics of doxycycline
1. 20% bound by serum proteins
2.60-70% absorption after oral administration
3.Absorption is impaired by divalent cations, Al3+, and antacids
4.Widely distributed especially into the CSF
Regarding agents used to treat gout
1.As little as 8mg of colchicine taken over 24 hours may be fatal
2.Allopurinol is a xanthine oxidase stimulator
3.Probenecid is an organic alkaline substance
4.Colchicine may precipitate acute attacks of gout
Regarding aspirin
1.The average anti-inflammatory dose of aspirin is 0.6g up to 4 hourly
2.Aspirin’s main side effect at usual doses is rash
3.Aspirin’s antiplatelet effect lasts 8 – 10 days
4.At low toxic doses – respiratory acidosis may occur
Regarding carbon monoxide poisoning
1.CO has an affinity for Hb that is about 2000 times that of oxygen
2.Hyperbaric oxygen is indicated as a treatment for all patients with CO Hb levels >20%
3.The average concentration of CO in the atmosphere is about 0.1ppm
4.With room air at 1atm the elimination half time of CO is about 80 minutes
Regarding mechanisms of antiviral drug action
1. Zidovudine is a protease inhibitor
2.Amantidine blocks viral DNA packaging and assembly
3.Indinavir is a reverse transcriptase inhibitor
4.Acyclovir inhibits viral DNA synthesis
Regarding NSAIDs
1.Piroxicam has a half life of >50 hours
2.Aspirin reversibly inhibits COX
3. Diclofenac is a selective COX1 inhibitor
4.Indomethacin is relatively free of adverse side effects
Regarding NSAIDs
1. At high doses diclofenac demonstrates zero order kinetics
2.Aspirin is a reversible inhibitor of cyclooxygenase
3. Aspirin at doses of <2g/day reduces uric acid levels
4.All NSAIDs can be found in synovial fluid after repeated dosing
Regarding paracetamol (acetaminophen)
1.Less than 5% is excreted unchanged
2.Acetaminophen has no anti-inflammatory properties
3.Haemolytic anaemia has rarely been noted with paracetamol
4.All of the above are true
Regarding the “azole†group of antifungals
1. Fluconazole has low water solubility
2. Ketoconazole may be given IV/PO
3.Clotrimazole is the treatment of choice for systemic candidiasis – given orally
4.They work by reduction of ergosterol synthesis by inhibition of fungal cytochrome P450 enzymes
Regarding the pharmacokinetics of the tetracyclines
1.Tetracyclines are 40 to 80 % bound by serum proteins
2.Absorption is enhanced by coadministration of antacids
3.Tetracyclines cross the blood brain barrier easily
4.Doxycycline is excreted predominantly by the kidney
Regarding toxicity of antibiotics
1. Enamel dysplasia is common with aminoglycosides
2.Gray baby syndrome occurs with rifampicin use
3.Haemolytic anaemias can occur with sulphonamide use
4.Nephritis is the most common adverse reaction with isoniazid
Resistance to B lactams
1.Can be due to an efflux pump
2.Is most commonly due to modification of the target PBPs
3. Does not involve penetration of drug to target PBPs
4. Infers resistance only to penicillinc
Resistance to Penicillin and other β lactams is due to
1.Impaired penetration of drug to target PBPs
2.Presence of an efflux pump
3. Inactivation of antibiotics by β lactamase
4.All of the above
Spironolactone
1.Has a steroid structure
2. Is a partial agonist
3.Promotes sodium retention
4. Increases potassium loss
The half life of a drug with a Vd of 200ml/70kg and clearance of 10â„“/hr/70kg is
1.10 hours
2.14 hours
3. 20 hours
4.40 hours
The main mechanism of action of colchicine is
1.Inhibition of polymorphonuclear leucocytes
2.Inhibition of synoviocyte phagocytosis
3.Reduced formation of leukotriene D4
4. Inhibition of mononuclear phagocytes
The metabolic pathway of detoxification that becomes increasingly important in paracetamol toxicity is
1.Conjugation with glucuronide
2.Oxidation
3.Reduction
4.Cytochrome p-450 dependent glutathione conjugation
Vancomycin
1.Is never orally administered as it is poorly absorbed from the GIT
2.60% of vancomycin is excreted by glomerular filtration
3.Parenteral vancomycin is commonly used for treatment of infections caused by methicillin susceptible staphylococci
4.Adverse reactions to vancomycin are encountered in about 10% of patients
Which of the following antidote – drug pairings is INCORRECT
1.Acetaminophen → n-acetyl cysteine
2.β blockers → glucagon
3.Opioids → naloxone
4.Tricyclic antidepressants → physostigmine
Which of the following drug overdoses may be amenable to the elimination technique of haemodialysis
1.Calcium channel blockers
2.Benzodiazepines
3.Valproate
4.Quinidine
Which of the following drugs cause diuresis by the mechanisms indicated?
1.Digoxin – by inhibiting release of ADH
2. Dopamine – by inhibiting active transport of chloride over the entire length of the descending limb of the loop of Henle
3.Frusemide – by inhibiting carbonic anhydrase
4.Chlorothiazide – by inhibiting active sodium transport in the ascending limb of the loop of Henle
Which of the following has a high extraction ratio
1.Trimethoprim
2.Valproic acid
3.Lignocaine
4.Metronidazole
Which of the following inhibits DNA gyrase?
1.Penicillin
2.Trimethoprim
3.Chloramphenicol
4.Ciprofloxacin
Which of the following NSAIDs has a t1/2 of about 1 hour
1.Diclofenac
2.Naproxen
3.Piroxicam
4.Indomethacin
Which of the following symptoms of aspirin toxicity occurs at plasmasalicylate concentrations of 100mg/dl?
1.Tinnitus
2.Vasomotor collapse
3.Metabolic acidosis
4.Gastric intolerance