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WorksheetsPharmacokinetics Quiz
Total questions: 20
Worksheet time: 10mins
Pharmacokinetic drug interactions occur due to changes in
Receptor binding
Drug absorption, distribution, metabolism or excretion
Drug efficacy only
Pharmacodynamics only
Enzyme induction leads to
Decreased drug metabolism
Increased drug levels
Increased drug metabolism
No change in drug action
Enzyme inhibition results in
Reduced drug levels
Increased clearance
Increased risk of toxicity
Shortened half-life
Which interaction affects drug absorption?
Chelation with antacids
Enzyme induction
Protein binding displacement
Receptor blockade
Phase III clinical trials are conducted to
Assess toxicity in animals
Assess safety in healthy volunteers
Confirm efficacy and monitor adverse effects in large patients
Post-marketing surveillance
Phase III trials usually involve
10–20 subjects
50–100 subjects
Several hundred to thousands
Only animals
Phase III trials are usually
Open-label
Uncontrolled
Randomized controlled trials
In vitro studies
Transdermal patches deliver drugs via
Oral route
Intramuscular route
Skin into systemic circulation
Intravenous route
Major advantage of transdermal patch is
First-pass metabolism
Fluctuating plasma levels
Prolonged and steady drug delivery
High dose requirement
Example of drug used as transdermal patch is
Insulin
Nitroglycerin
Heparin
Penicillin
Fixed Dose Combination (FDC) means
Variable dose drugs combined
Single drug in multiple doses
Combination of two or more drugs in fixed ratio
Drug with antidote
Rational FDC example is
Amoxicillin + clavulanic acid
Paracetamol + ranitidine
Ampicillin + cloxacillin + steroid
NSAID + antihistamine
Irrational FDC example is
Levodopa + carbidopa
Trimethoprim + sulfamethoxazole
NSAID + muscle relaxant
Amoxicillin + clavulanic acid
Special drug delivery systems aim to
Increase toxicity
Reduce patient compliance
Target drug delivery and improve efficacy
Increase dosing frequency
Liposomal drug delivery system is mainly used to
Increase renal clearance
Reduce drug toxicity and target tissues
Increase oral absorption
Decrease stability
Nanoparticles in drug delivery help in
Random distribution
Targeted and sustained release
Reducing bioavailability
Increasing first-pass metabolism
Osmotic pump tablets provide
Immediate drug release
Erratic absorption
Controlled drug release
Short duration action
Pharmacokinetic interaction at protein binding site leads to
Decreased free drug
Increased free drug
No change
Drug inactivation
Grapefruit juice interaction mainly affects
Drug absorption via CYP3A4 inhibition
Renal excretion
Protein binding
Receptor affinity
Post-marketing surveillance of drugs is done in
Phase I
Phase II
Phase III
Phase IV
