Cathartics: Kaolin MCQs With Answer

Cathartics: Kaolin MCQs With Answer

Kaolin is a pharmaceutically important clay primarily used as an adsorbent and antidiarrheal rather than a true cathartic, but understanding its role in gastrointestinal therapy is vital for B. Pharm students. This focused MCQ set explores kaolin’s chemistry, mechanism of adsorption, formulation with pectin, pharmacokinetics, therapeutic uses, dose calculations, adverse effects, drug interactions, quality control tests, and regulatory considerations. Questions emphasize applied pharmacology, compounding practice, patient counseling, and exam-ready concepts. Ideal for revision and deeper learning, these MCQs will strengthen clinical reasoning and formulation knowledge related to cathartics and antidiarrheal agents. Now let’s test your knowledge with 50 MCQs on this topic.

Q1. What is the primary pharmaceutical action of kaolin in gastrointestinal disorders?

• Lubricant laxative
• Osmotic cathartic
• Adsorbent and antidiarrheal
• Prokinetic agent

Correct Answer: Adsorbent and antidiarrheal

Q2. Kaolin is chemically classified as which type of compound?

• Aluminosilicate clay
• Calcium carbonate
• Synthetic polymer
• Activated charcoal

Correct Answer: Aluminosilicate clay

Q3. Which of the following best describes kaolin’s mechanism of action?

• Neutralizes stomach acid by releasing bicarbonate
• Adsorbs toxins and excess fluids in the gut lumen
• Stimulates intestinal peristalsis via cholinergic receptors
• Acts as an osmotic agent by drawing water into the bowel

Correct Answer: Adsorbs toxins and excess fluids in the gut lumen

Q4. Kaolin is commonly combined with which polysaccharide to form an oral antidiarrheal preparation?

• Pectin
• Starch
• Carboxymethylcellulose
• Gelatin

Correct Answer: Pectin

Q5. In formulation science, kaolin’s surface area and particle size most directly influence what property?

• Melting point
• Adsorptive capacity
• Boiling point
• Optical rotation

Correct Answer: Adsorptive capacity

Q6. Which is a common adverse effect associated with excessive oral kaolin use?

• Hypoglycemia
• Constipation and possible intestinal obstruction
• Tachycardia
• Bronchospasm

Correct Answer: Constipation and possible intestinal obstruction

Q7. Kaolin has the highest utility in which clinical situation?

• Chronic idiopathic constipation
• Acute secretory diarrhea with suspected toxins
• Paralytic ileus
• Peptic ulcer bleeding

Correct Answer: Acute secretory diarrhea with suspected toxins

Q8. Which pharmacokinetic statement about kaolin is correct?

• Kaolin is systemically absorbed and metabolized in the liver
• Kaolin remains in the gastrointestinal lumen with minimal systemic absorption
• Kaolin is rapidly excreted via the kidneys after absorption
• Kaolin undergoes enterohepatic recirculation

Correct Answer: Kaolin remains in the gastrointestinal lumen with minimal systemic absorption

Q9. Which quality control test is relevant for pharmaceutical kaolin?

• Assay by HPLC for active principle content
• X-ray diffraction to confirm mineralogical identity
• Gas chromatography for volatile impurities
• pH titration for acidity equivalent

Correct Answer: X-ray diffraction to confirm mineralogical identity

Q10. Which interaction is most likely when kaolin is given concomitantly with oral drugs?

• Increased bioavailability due to complexation
• Reduced absorption of certain drugs due to adsorption onto kaolin
• Acceleration of hepatic metabolism via enzyme induction
• None — kaolin has no effect on oral drug absorption

Correct Answer: Reduced absorption of certain drugs due to adsorption onto kaolin

Q11. Which analytical property differentiates kaolin from bentonite?

• Kaolin is a montmorillonite clay while bentonite is kaolinite
• Kaolin has lower cation exchange capacity than bentonite
• Bentonite is chemically pure silica while kaolin contains alumina
• Kaolin exhibits high swelling in water compared to bentonite

Correct Answer: Kaolin has lower cation exchange capacity than bentonite

Q12. What is the typical role of kaolin in pediatric antidiarrheal mixtures historically?

• Systemic antibiotic replacement
• Adsorbent to bind toxins and reduce stool liquidity
• Strong cathartic to rapidly clear the gut
• Probiotic to restore gut flora

Correct Answer: Adsorbent to bind toxins and reduce stool liquidity

Q13. Which statement about kaolin’s effect on stool is accurate?

• It softens stool by increasing water retention
• It forms a protective coating and reduces stool liquidity
• It directly kills enteric pathogens in the mucosa
• It acts as an intestinal stimulant to increase stool frequency

Correct Answer: It forms a protective coating and reduces stool liquidity

Q14. During compounding, which excipient is commonly used to suspend kaolin for oral syrups?

• Sorbitol
• Glycerin
• Carboxymethylcellulose (CMC)
• Magnesium stearate

Correct Answer: Carboxymethylcellulose (CMC)

Q15. Which laboratory identification test is most specific for kaolinite mineral in kaolin?

• Loss on drying
• X-ray diffraction pattern showing kaolinite peaks
• pH measurement
• Colorimetric test for iron

Correct Answer: X-ray diffraction pattern showing kaolinite peaks

Q16. Kaolin’s adsorptive capacity is best described by which adsorption model in pharmaceutical contexts?

• Michaelis-Menten kinetics
• Langmuir adsorption isotherm
• Henderson-Hasselbalch equation
• Nernst-Planck equation

Correct Answer: Langmuir adsorption isotherm

Q17. In which patient should kaolin be used cautiously or avoided?

• Patient with mild acute diarrhea
• Patient with suspected intestinal obstruction
• Patient requiring topical skin treatment
• Patient with seasonal allergies

Correct Answer: Patient with suspected intestinal obstruction

Q18. What is a correct counseling point when dispensing kaolin-pectin syrup?

• Take immediately before meals for best effect
• Separate dosing from other oral medications to reduce interaction risk
• It is safe to use with all antibiotics without concern
• It may cause central nervous system depression

Correct Answer: Separate dosing from other oral medications to reduce interaction risk

Q19. Which regulatory classification best fits kaolin in many pharmacopeias?

• Official bulk active pharmaceutical ingredient (API) with monograph
• Controlled substance requiring special license
• Parenteral sterile drug product
• Unregulated food additive only

Correct Answer: Official bulk active pharmaceutical ingredient (API) with monograph

Q20. Which physicochemical property of kaolin contributes to its low systemic toxicity?

• High solubility in gastrointestinal fluids
• High systemic absorption across the intestinal mucosa
• Insolubility and confinement to the GI lumen
• Rapid metabolic activation

Correct Answer: Insolubility and confinement to the GI lumen

Q21. Which of these is a likely result of prolonged kaolin ingestion?

• Iron deficiency anemia due to binding of dietary iron
• Hyperkalemia due to potassium retention
• Improved systemic antibiotic levels
• Excessive hydration

Correct Answer: Iron deficiency anemia due to binding of dietary iron

Q22. How does kaolin differ from activated charcoal in clinical use?

• Kaolin is mainly used for systemic poisoning, charcoal for diarrhea
• Both have identical pore structures and adsorption spectra
• Kaolin is used mainly as an antidiarrheal adsorbent; charcoal is used for emergency toxin adsorption
• Charcoal stimulates GI motility while kaolin inhibits it

Correct Answer: Kaolin is used mainly as an antidiarrheal adsorbent; charcoal is used for emergency toxin adsorption

Q23. Which storage condition is most appropriate for kaolin powder in the pharmacy?

• High humidity and open containers
• Dry, airtight containers protected from moisture
• Refrigerated at 2–8°C
• Frozen at -20°C

Correct Answer: Dry, airtight containers protected from moisture

Q24. Which test helps determine microbial safety of kaolin oral formulations?

• Total viable aerobic microbial count
• UV-Vis spectroscopy for assay
• Chromatography for heavy metals only
• Titration for acid value

Correct Answer: Total viable aerobic microbial count

Q25. In which formulation would kaolin most likely be used as an excipient rather than an active agent?

• Topical skin paste for burn wounds
• Tablet diluent or filler in some oral solids
• Intravenous infusion solution
• Inhalation aerosol suspension

Correct Answer: Tablet diluent or filler in some oral solids

Q26. Which of the following is a correct statement about kaolin and pregnancy?

• Kaolin is contraindicated in all pregnant patients
• Kaolin has minimal systemic absorption and is generally considered low risk but use under medical advice
• Kaolin causes teratogenic effects in the first trimester
• Kaolin is a hormonal drug affecting pregnancy

Correct Answer: Kaolin has minimal systemic absorption and is generally considered low risk but use under medical advice

Q27. Which heavy metal contaminant is of most concern in kaolin samples and must be controlled?

• Lead
• Sodium
• Potassium
• Chloride

Correct Answer: Lead

Q28. Which symptom should prompt discontinuation of kaolin therapy and immediate medical evaluation?

• Temporary dry mouth
• Persistent abdominal pain and vomiting suggesting obstruction
• Slight temporary dizziness
• Transient increased appetite

Correct Answer: Persistent abdominal pain and vomiting suggesting obstruction

Q29. Kaolin’s role in combined antidiarrheal formulations is primarily to:

• Induce bowel movements
• Provide systemic anti-inflammatory action
• Adsorb pathogens, toxins, and excess fluid to firm stools
• Act as a source of dietary calcium

Correct Answer: Adsorb pathogens, toxins, and excess fluid to firm stools

Q30. Which analytical method is useful to quantify inorganic contaminants in kaolin?

• ICP-MS (Inductively Coupled Plasma Mass Spectrometry)
• Polarimetry
• Gel electrophoresis
• Microbiological plate count

Correct Answer: ICP-MS (Inductively Coupled Plasma Mass Spectrometry)

Q31. When teaching B. Pharm students about kaolin, emphasizing which principle is most important?

• Kaolin’s systemic pharmacodynamic receptor binding
• Principles of adsorption, formulation, and patient counseling
• Kaolin as a primary antibiotic therapy
• Advanced steroid synthesis from kaolin

Correct Answer: Principles of adsorption, formulation, and patient counseling

Q32. Which is a correct note about kaolin’s effect on oral vaccine efficacy if co-administered?

• No possible effect on oral vaccines
• Kaolin may adsorb vaccine antigens in the gut and reduce efficacy
• Kaolin enhances vaccine uptake across mucosa
• Kaolin converts vaccines to more potent forms

Correct Answer: Kaolin may adsorb vaccine antigens in the gut and reduce efficacy

Q33. Which formulation parameter is critical when preparing a kaolin suspension to ensure uniform dosing?

• Particle wettability and viscosity control to prevent rapid settling
• Increase in pH to extreme alkaline range
• High alcohol content for solubility
• Use of volatile solvents

Correct Answer: Particle wettability and viscosity control to prevent rapid settling

Q34. In a drug-excipient compatibility study, what outcome would indicate kaolin is incompatible with an oral drug?

• No change in drug content or physical appearance
• Significant decrease in drug potency and formation of new degradation products
• Improved dissolution rate without degradation
• Enhanced tablet hardness only

Correct Answer: Significant decrease in drug potency and formation of new degradation products

Q35. Which property of kaolin is exploited in topical pastes and poultices?

• High systemic absorption
• Its ability to form a protective, absorbent coating
• Catalytic enzymatic activity
• High solubility in lipids

Correct Answer: Its ability to form a protective, absorbent coating

Q36. Which formulation would least likely include kaolin?

• Oral antidiarrheal syrup
• Topical anti-inflammatory cream for rashes
• Intravenous electrolyte solution
• Tablet excipient mix for oral solids

Correct Answer: Intravenous electrolyte solution

Q37. Which laboratory parameter is used to evaluate swelling and dispersibility of clay excipients like kaolin?

• Sedimentation volume
• Melting point
• Optical rotation
• Vapor pressure

Correct Answer: Sedimentation volume

Q38. Which clinical trial outcome would support using kaolin in a diarrheal disease protocol?

• Increased stool frequency and duration of disease
• Reduced stool volume, decreased frequency, and faster recovery time
• Significant systemic side effects with no symptomatic benefit
• Higher hospitalization rates compared to placebo

Correct Answer: Reduced stool volume, decreased frequency, and faster recovery time

Q39. Which term best describes kaolin when used to remove toxins from the gastrointestinal tract?

• Chelating agent
• Adsorbent
• Enzyme inhibitor
• Osmotic laxative

Correct Answer: Adsorbent

Q40. What is an important formulation consideration when adding kaolin to flavored syrups for palatability?

• Kaolin is highly sweet and needs no flavoring
• Masking undesirable chalky taste using appropriate flavoring and sweeteners
• Kaolin increases volatility of flavors
• Ensure syrups are extremely acidic to solubilize kaolin

Correct Answer: Masking undesirable chalky taste using appropriate flavoring and sweeteners

Q41. Which scientific principle explains why kaolin may reduce the effectiveness of orally administered tetracyclines?

• Formation of insoluble complexes via chelation or adsorption
• Enzyme induction by kaolin leading to rapid metabolism
• Kaolin increases gastric motility, reducing absorption time
• Kaolin converts tetracyclines into active metabolites

Correct Answer: Formation of insoluble complexes via chelation or adsorption

Q42. Which specification would not typically be part of a kaolin monograph?

• Loss on drying
• X-ray diffraction pattern
• Assay for organic active pharmaceutical ingredient by HPLC
• Limits for heavy metals

Correct Answer: Assay for organic active pharmaceutical ingredient by HPLC

Q43. What is the rationale for advising separation of kaolin from oral antibiotics by at least 2 hours?

• To allow kaolin to be metabolized systemically first
• To prevent kaolin from adsorbing and reducing antibiotic absorption
• To potentiate antibiotic action via kaolin synergy
• To enhance kaolin’s taste masking

Correct Answer: To prevent kaolin from adsorbing and reducing antibiotic absorption

Q44. Which process can reduce heavy metal levels in kaolin raw materials during manufacturing?

• Acid leaching and purification steps
• Increasing particle size without washing
• Drying at low temperatures only
• Adding metal salts to bind impurities

Correct Answer: Acid leaching and purification steps

Q45. Which of the following best describes kaolin’s pH behavior in aqueous suspension?

• Strongly basic, pH > 12
• Inert to pH and always neutral at pH 7
• Typically slightly acidic to neutral depending on impurities
• Strongly acidic, pH < 2

Correct Answer: Typically slightly acidic to neutral depending on impurities

Q46. When assessing a kaolin-based antidiarrheal in a clinical pharmacy exam, which outcome measure is most relevant?

• Time to first bowel movement in constipation
• Reduction in stool frequency and improvement in stool consistency in diarrhea
• Increase in blood pressure
• Increase in systemic antibiotic plasma levels

Correct Answer: Reduction in stool frequency and improvement in stool consistency in diarrhea

Q47. Which patient education point applies to kaolin use in elderly patients?

• Elderly patients never experience constipation from kaolin
• Monitor for decreased drug absorption and constipation; adjust concomitant medications accordingly
• Kaolin will cure chronic inflammatory bowel disease
• Kaolin should be used IV in elderly for better effect

Correct Answer: Monitor for decreased drug absorption and constipation; adjust concomitant medications accordingly

Q48. In research settings, which surface characterization technique helps evaluate kaolin adsorptive properties?

• BET surface area analysis
• Mass spectrometry for proteins
• Nuclear magnetic resonance of liquids only
• Blood gas analysis

Correct Answer: BET surface area analysis

Q49. Which statement correctly contrasts cathartics and kaolin-based antidiarrheals?

• Cathartics and kaolin serve identical mechanisms of increasing stool bulk
• Cathartics promote bowel evacuation; kaolin adsorbs toxins and firms stool without promoting evacuation
• Kaolin is a systemic stimulant of intestinal smooth muscle like stimulant laxatives
• Cathartics decrease intestinal water content while kaolin increases it

Correct Answer: Cathartics promote bowel evacuation; kaolin adsorbs toxins and firms stool without promoting evacuation

Q50. For a B. Pharm student preparing for exams, which integrated topic related to kaolin should be prioritized?

• Mechanisms of adsorption, formulation design of suspensions/pastes, drug–excipient interactions, and clinical counseling points
• Advanced organic synthesis pathways of kaolin
• Kaolin’s role as a systemic enzyme inhibitor
• Parenteral dosing regimens for kaolin

Correct Answer: Mechanisms of adsorption, formulation design of suspensions/pastes, drug–excipient interactions, and clinical counseling points

G S Sachin

I am a Registered Pharmacist under the Pharmacy Act, 1948, and the founder of PharmacyFreak.com. I hold a Bachelor of Pharmacy degree from Rungta College of Pharmaceutical Science and Research. With a strong academic foundation and practical knowledge, I am committed to providing accurate, easy-to-understand content to support pharmacy students and professionals. My aim is to make complex pharmaceutical concepts accessible and useful for real-world application.

Mail- Sachin@pharmacyfreak.com