Weightage is measured from previous Drug Inspector papers, not estimated. Question counts are read from the live bank when this page is built.
Subtopics in this bank
ADMEAUC calculationAUC/AUMC/MRTBCS classificationBCS classification and bioavailability predictionBCS classification characteristicsBioavailabilityBioavailability & bioequivalenceBioavailability metricsBioequivalenceClearanceCompartment modelsDissolution and route of administrationDosage-regimen designDrug absorptionDrug distributionDrug metabolismFactors affecting oral bioavailabilityFirst-passFirst-pass / distributionHalf-life conceptHalf-life, clearance, VdIVIVCIVIVC and biowaiver applicationsNon-linear PKPK fundamentalsPharmacokinetic sequenceProtein bindingSteady-stateSteady-state kinetics in repeated dosingTransport mechanismsVolume of distributionZero vs first order
Sample questions, with the reasoning
Every question in the bank is explained like this — including why each wrong option is wrong.
A drug is 55% bound to plasma proteins. The concentration of drug in a patient's body after 10 hours was found to be 20 mg/L. The apparent volume of distribution was found to be 0.60 kg/L for an 80 kg patient. What is the total amount of drug present in the patient's body after 10 hours?
A)120 mg
B)960 mg✓
C)1.5 mg
D)20 mg
Why B is correct
Total Vd (L) = 0.60 L/kg x 80 kg = 48 L. Amount in body = Vd x C = 48 L x 20 mg/L = 960 mg. (Plasma protein binding % is a distractor here — amount in body is calculated directly from Vd and total plasma concentration.)
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A drug of low water solubility when given orally is absorbed up to 90% of the administered dose. The drug belongs to which class according to BCS classification?
A)Class III
B)Class I
C)Class II✓
D)Class IV
Why C is correct
BCS Class II drugs are low solubility but high permeability — the high (90%) fraction absorbed indicates good membrane permeability despite poor aqueous solubility, matching Class II exactly.
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A new drug with high bioavailability is being developed. Which factor is most critical in determining the appropriate loading dose for this drug?
A)The drug's molecular weight, which affects its solubility in the bloodstream.
B)The therapeutic index of the drug, which defines its safety margin.
C)The drug's bioavailability, which dictates how much of the administered dose reaches systemic circulation.✓
D)The solubility of the drug in the gastrointestinal tract, which affects absorption rate.
Why C is correct
Loading dose is calculated to achieve therapeutic concentrations rapidly. Since bioavailability determines the proportion of the dose that becomes active in the bloodstream, it directly impacts how much drug is needed to reach the desired effect.
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Practise S11 with real marking
90 questions · −1/3 negative marking · explanations after every answer. No sign-up needed to try.