Advantages and disadvantages of GRDDS MCQs With Answer

Advantages and disadvantages of GRDDS MCQs With Answer helps M. Pharm students consolidate critical understanding of gastroretentive drug delivery systems (GRDDS), a key platform in Drug Delivery Systems (MPH 102T). GRDDS aim to prolong gastric residence and release drugs in a controlled manner within the stomach, offering clear advantages for drugs with a narrow absorption window, weak bases with pH-dependent solubility, and for local gastric therapy (e.g., H. pylori eradication, GERD). However, these systems face challenges such as variability in gastric emptying, food effects, risk of gastric irritation, and suitability constraints. The following MCQs probe mechanism-linked pros and cons across floating, high-density, mucoadhesive, expandable, magnetic, and raft-forming GRDDS, emphasizing clinical relevance, formulation design, and patient-related factors.

Q1. Which is a primary advantage of GRDDS in systemic therapy?

• Enhanced bioavailability of drugs with a narrow absorption window in the upper small intestine
• Complete avoidance of hepatic first-pass metabolism
• Elimination of inter-subject variability in gastric emptying
• Increased colonic residence time for colon-specific drugs

Correct Answer: Enhanced bioavailability of drugs with a narrow absorption window in the upper small intestine

Q2. Which drug property most benefits from gastroretention due to gastric acidity?

• Weakly basic, pH-dependent solubility (BCS class II)
• Highly acid-labile peptides
• Weak acids with higher solubility at high pH
• Drugs maximally absorbed in the colon

Correct Answer: Weakly basic, pH-dependent solubility (BCS class II)

Q3. Which is a distinct advantage of GRDDS for local therapy?

• Improved eradication of Helicobacter pylori using antibiotic-loaded GRDDS
• Enhanced delivery of mesalamine to the colon
• Reduced risk of gastric irritation by NSAIDs
• Instant relief of acute pain via rapid absorption

Correct Answer: Improved eradication of Helicobacter pylori using antibiotic-loaded GRDDS

Q4. Which of the following drugs are generally unsuitable for GRDDS because of acid lability?

• Insulin and erythromycin base
• Metformin and amoxicillin
• Riboflavin and levodopa
• Furosemide and ciprofloxacin

Correct Answer: Insulin and erythromycin base

Q5. Which physiological condition most compromises the in vivo performance of floating GRDDS?

• Fasted state with strong migrating motor complex (MMC) activity
• Fed state with high-fat meal
• Slightly elevated gastric viscosity
• Gastric pH below 3

Correct Answer: Fasted state with strong migrating motor complex (MMC) activity

Q6. What is a key disadvantage of GRDDS when formulating very high-dose drugs?

• Requirement of bulky dosage form to achieve both floatation and sustained release
• Improved patient adherence due to reduced frequency
• Lower risk of dose dumping in acidic media
• Greater suitability for highly potent drugs

Correct Answer: Requirement of bulky dosage form to achieve both floatation and sustained release

Q7. Which statement best reflects the food-effect limitation of many GRDDS?

• Performance may depend on meal timing and composition, causing variability
• GRDDS performance is completely independent of the fed/fasted state
• High-fat meals always reduce gastric retention time of GRDDS
• Liquids have no effect on buoyancy or retention

Correct Answer: Performance may depend on meal timing and composition, causing variability

Q8. In which patient condition are GRDDS potentially contraindicated due to safety concerns?

• History of gastric outlet obstruction or pyloric stenosis
• Mild hypertension
• Corrected hypothyroidism
• Myopia

Correct Answer: History of gastric outlet obstruction or pyloric stenosis

Q9. Which drug types are generally unsuitable for GRDDS because of a high risk of local gastric irritation?

• Potassium chloride and ferrous sulfate
• Clarithromycin and amoxicillin
• Metformin and propranolol
• Riboflavin and baclofen

Correct Answer: Potassium chloride and ferrous sulfate

Q10. Which system-level advantage may result from effective gastroretention with controlled release?

• Reduced plasma concentration fluctuations through controlled input from the stomach
• Rapid onset irrespective of dosage form design
• Complete protection from gastric enzymatic degradation
• Reduced inter-occasion variability in hepatic clearance

Correct Answer: Reduced plasma concentration fluctuations through controlled input from the stomach

Q11. What is a key limitation of mucoadhesive GRDDS?

• Mucus turnover and shear can detach the dosage form, shortening residence
• Independence from gastric motility patterns
• Unlimited drug loading without affecting adhesion
• No risk of local mucosal damage with strong adhesives

Correct Answer: Mucus turnover and shear can detach the dosage form, shortening residence

Q12. Which is an advantage of high-density (sinking) GRDDS compared to floating systems?

• Less dependent on gastric fluid volume and gas generation
• Require lower material density than gastric fluid
• Always provide longer retention than mucoadhesive systems
• Are unaffected by patient posture or fed/fasted state

Correct Answer: Less dependent on gastric fluid volume and gas generation

Q13. Which is a principal disadvantage of expandable gastroretentive systems?

• Risk of gastric obstruction if dosage form fails to reduce below pyloric size before emptying
• Guaranteed zero-order release irrespective of polymer properties
• Complete independence from gastric pH for every drug
• No need to evaluate mechanical integrity during peristalsis

Correct Answer: Risk of gastric obstruction if dosage form fails to reduce below pyloric size before emptying

Q14. What is a practical limitation of magnetic GRDDS?

• Necessity of an external magnet and precise alignment for retention
• Inability to include poorly soluble weak bases
• Incompatibility with commonly used polymers
• Complete independence from patient compliance

Correct Answer: Necessity of an external magnet and precise alignment for retention

Q15. What is a major advantage of raft-forming GRDDS?

• Useful for sustained local therapy in GERD by forming a floating viscous barrier
• Ideal for delivering high-dose, systemic drugs with a narrow therapeutic index
• Superior to all other GRDDS for minimizing food effects
• Provides reliable retention even in the fasted MMC phase

Correct Answer: Useful for sustained local therapy in GERD by forming a floating viscous barrier

Q16. Which of the following is least suitable for GRDDS from a targeting perspective?

• Mesalamine intended for colonic release
• Amoxicillin for H. pylori therapy
• Levodopa absorbed in proximal small intestine
• Riboflavin with narrow upper GI window

Correct Answer: Mesalamine intended for colonic release

Q17. Which is a critical operational requirement—and practical disadvantage—of floating systems?

• Sufficient gastric fluid volume (e.g., 200–250 mL water) to enable buoyancy
• Complete absence of CO₂ generation
• Density greater than gastric fluid
• Independence from patient posture

Correct Answer: Sufficient gastric fluid volume (e.g., 200–250 mL water) to enable buoyancy

Q18. Which development challenge reflects a disadvantage in predicting GRDDS performance?

• Standard dissolution tests poorly simulate gastric motility and emptying patterns
• Scale-up is trivial due to simple hydrophilic matrices
• In vitro buoyancy predicts in vivo retention precisely
• Regulatory bioequivalence is unnecessary for GRDDS

Correct Answer: Standard dissolution tests poorly simulate gastric motility and emptying patterns

Q19. Which of the following is a misconception and therefore not an advantage of GRDDS?

• Avoidance of hepatic first-pass metabolism
• Improved bioavailability for narrow absorption window drugs
• Potential reduction in dosing frequency
• Enhanced local gastric action

Correct Answer: Avoidance of hepatic first-pass metabolism

Q20. Compared to single-unit tablets, what is a key advantage of multi-unit (multiparticulate) GRDDS?

• Multi-unit systems reduce the risk of dose dumping and unpredictable emptying compared to single-unit forms
• Single-unit forms always show lower variability than multiparticulates
• Multi-unit systems cannot be designed to float
• Single-unit systems never cause gastric irritation

Correct Answer: Multi-unit systems reduce the risk of dose dumping and unpredictable emptying compared to single-unit forms

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