Anti-inflammatory agents – Antipyrine MCQs With Answer

Anti-inflammatory agents – Antipyrine MCQs With Answer provides B. Pharm students a focused review of antipyrine within the broader class of anti-inflammatory and analgesic agents. This concise, keyword-rich introduction covers antipyrine chemistry, mechanism of action, pharmacokinetics, therapeutic uses, adverse effects, interactions and formulation aspects relevant to pharmacy practice. Emphasis is placed on enzyme induction, hepatic metabolism, clinical indications and safety monitoring so students gain practical, exam-ready insights. These MCQs are crafted to deepen understanding beyond basics and reinforce critical thinking for case-based questions and viva voce examinations. Now let’s test your knowledge with 50 MCQs on this topic.

Q1. What is the chemical class to which antipyrine belongs?

• Salicylate derivative
• Pyrazolone derivative
• Propionic acid derivative
• Oxicam derivative

Correct Answer: Pyrazolone derivative

Q2. The primary pharmacological actions of antipyrine include:

• Strong peripheral anti-inflammatory and COX-2 selective inhibition
• Analgesic, antipyretic and weak anti-inflammatory effects
• Antibiotic and antiviral properties
• Local anesthetic and muscle relaxant effects

Correct Answer: Analgesic, antipyretic and weak anti-inflammatory effects

Q3. Antipyrine is commonly used clinically as:

• A first-line oral NSAID for chronic arthritis
• An otic analgesic component in ear preparations
• A topical antifungal agent
• A long-acting anticoagulant

Correct Answer: An otic analgesic component in ear preparations

Q4. Which metabolic property made antipyrine useful historically as a probe drug?

• It is excreted unchanged in urine
• Its clearance is sensitive to hepatic microsomal enzyme induction
• It is a specific substrate for renal transporters
• It undergoes enterohepatic recycling exclusively

Correct Answer: Its clearance is sensitive to hepatic microsomal enzyme induction

Q5. The major route of elimination for antipyrine is:

• Renal excretion of unchanged drug
• Metabolism by hepatic enzymes followed by renal excretion
• Exhalation via lungs
• Biliary excretion of unchanged drug

Correct Answer: Metabolism by hepatic enzymes followed by renal excretion

Q6. Which hepatic enzyme system predominantly metabolizes antipyrine?

• Monoamine oxidase (MAO)
• Cytochrome P450 microsomal enzymes
• Alcohol dehydrogenase
• Glutathione-S-transferase exclusively

Correct Answer: Cytochrome P450 microsomal enzymes

Q7. Antipyrine’s analgesic and antipyretic effects are primarily mediated by:

• Inhibition of peripheral prostaglandin synthesis only
• Central inhibition of prostaglandin synthesis and modulation of hypothalamic set point
• Blockade of NMDA receptors
• Activation of opioid receptors

Correct Answer: Central inhibition of prostaglandin synthesis and modulation of hypothalamic set point

Q8. A known hematological adverse effect associated with some pyrazolone derivatives (including antipyrine analogs) is:

• Megakaryocytic hyperplasia
• Agranulocytosis
• Polycythemia vera
• Hypereosinophilia only

Correct Answer: Agranulocytosis

Q9. Which patient condition is a contraindication or requires caution when using antipyrine-containing preparations?

• G6PD deficiency due to risk of hemolysis
• Hyperthyroidism without any precautions
• Controlled hypertension with no other comorbidities
• Well-controlled type 2 diabetes

Correct Answer: G6PD deficiency due to risk of hemolysis

Q10. Antipyrine’s pH partitioning and moderate lipophilicity imply which of the following pharmacokinetic characteristics?

• Extremely high renal clearance with no hepatic metabolism
• Good oral absorption and wide tissue distribution
• Poor absorption and minimal tissue distribution
• Exclusive distribution in plasma only

Correct Answer: Good oral absorption and wide tissue distribution

Q11. Which formulation commonly contains antipyrine for topical application?

• Otic drops combined with benzocaine
• Oral sustained-release tablets for chronic pain
• Intravenous infusion for acute analgesia
• Topical antifungal cream

Correct Answer: Otic drops combined with benzocaine

Q12. In pharmacokinetic studies, antipyrine clearance decreases when co-administered with which type of drug?

• Potent CYP inducers
• Potent CYP inhibitors
• Highly protein-bound drugs with no CYP interactions
• Laxatives that increase gastrointestinal transit

Correct Answer: Potent CYP inhibitors

Q13. The use of antipyrine as a probe for hepatic function is primarily because it:

• Undergoes rapid renal filtration
• Is metabolized by multiple CYP isoforms and reflects overall microsomal activity
• Is not metabolized and accumulates in plasma
• Is selectively metabolized by a single minor enzyme

Correct Answer: Is metabolized by multiple CYP isoforms and reflects overall microsomal activity

Q14. Which adverse effect is most characteristically monitored when patients take pyrazolone derivatives?

• Renal papillary necrosis without warning signs
• Hepatotoxicity and blood dyscrasias
• Hyperglycemia and glucose intolerance
• Pulmonary fibrosis acutely

Correct Answer: Hepatotoxicity and blood dyscrasias

Q15. Antipyrine can potentiate the effects of warfarin by which mechanism?

• Increasing vitamin K synthesis in gut flora
• Inhibiting warfarin metabolism via CYP interactions
• Directly displacing warfarin from clotting factors
• Stimulating platelet aggregation

Correct Answer: Inhibiting warfarin metabolism via CYP interactions

Q16. Which laboratory monitoring is advisable when a patient uses systemic pyrazolone therapy long-term?

• Serial CBC and liver function tests
• Only fasting blood glucose
• Serum cholesterol annually only
• Urinalysis for ketones only

Correct Answer: Serial CBC and liver function tests

Q17. The structural feature that defines antipyrine is the presence of:

• A benzene sulfonamide moiety
• A pyrazolone ring system
• A carboxylic acid group as in classical NSAIDs
• A long-chain fatty acid ester

Correct Answer: A pyrazolone ring system

Q18. Which statement about antipyrine’s anti-inflammatory potency compared to classical NSAIDs such as ibuprofen is true?

• Antipyrine has stronger peripheral anti-inflammatory action than ibuprofen
• Antipyrine has weaker peripheral anti-inflammatory activity than ibuprofen
• Both have equal COX-2 selectivity and potency
• Antipyrine is solely an anti-inflammatory with no analgesic effect

Correct Answer: Antipyrine has weaker peripheral anti-inflammatory activity than ibuprofen

Q19. The bioavailability of antipyrine when given orally is primarily influenced by:

• First-pass hepatic metabolism
• Non-enzymatic degradation in stomach only
• Extensive binding to erythrocytes preventing absorption
• Immediate secretion into bile without absorption

Correct Answer: First-pass hepatic metabolism

Q20. Which symptom would most likely indicate a serious hypersensitivity reaction to a pyrazolone derivative?

• Mild transient headache
• Agranulocytosis manifesting as fever, sore throat and infection
• Temporary mild nausea for one dose only
• Localized itching at application site resolving quickly

Correct Answer: Agranulocytosis manifesting as fever, sore throat and infection

Q21. In neonates and infants, antipyrine pharmacokinetics differ mainly due to:

• Faster hepatic metabolism than adults
• Immature hepatic enzyme systems leading to prolonged half-life
• Complete absence of renal excretion mechanisms
• Exclusively topical distribution with no systemic absorption

Correct Answer: Immature hepatic enzyme systems leading to prolonged half-life

Q22. A drug interaction that induces hepatic enzymes will affect antipyrine by:

• Increasing its half-life and plasma concentrations
• Decreasing its half-life and plasma concentrations
• Preventing its absorption from the gut
• Causing direct renal toxicity

Correct Answer: Decreasing its half-life and plasma concentrations

Q23. Which clinical scenario would justify topical otic use of antipyrine rather than systemic therapy?

• Generalized musculoskeletal pain
• Local ear pain with tympanic membrane intact and minor inflammation
• Severe systemic fever of unknown origin
• Chronic rheumatoid arthritis requiring systemic control

Correct Answer: Local ear pain with tympanic membrane intact and minor inflammation

Q24. The analgesic mechanism of antipyrine involves inhibition of which mediator synthesis centrally?

• Nitric oxide synthase exclusively
• Prostaglandin synthesis via central cyclooxygenase inhibition
• Serotonin reuptake inhibition only
• Release of histamine from mast cells

Correct Answer: Prostaglandin synthesis via central cyclooxygenase inhibition

Q25. Which pharmacodynamic property explains antipyrine’s antipyretic action?

• Peripheral vasoconstriction increasing heat retention
• Resetting hypothalamic thermoregulatory center by lowering prostaglandin E2 synthesis
• Increasing thyroid hormone release
• Blocking sweat glands directly

Correct Answer: Resetting hypothalamic thermoregulatory center by lowering prostaglandin E2 synthesis

Q26. When assessing an antipyrine-containing ear drop, which excipient is often combined to provide local analgesia?

• Benzocaine
• Diphenhydramine
• Metformin
• Furosemide

Correct Answer: Benzocaine

Q27. Which metabolic reaction is commonly involved in antipyrine biotransformation?

• Glucuronidation and hydroxylation
• Direct acetylation without oxidation
• Complete methylation only
• Formation of glycosides in liver

Correct Answer: Glucuronidation and hydroxylation

Q28. A pharmacology student studying drug interactions should be aware that antipyrine metabolism is influenced by which common inducer?

• Rifampicin (rifampin)
• Amoxicillin without clavulanic acid
• Insulin therapy
• Vitamin C supplementation

Correct Answer: Rifampicin (rifampin)

Q29. In clinical toxicology, which acute presentation might suggest antipyrine overdose?

• Profound respiratory depression only
• Nausea, vomiting, dizziness and CNS depression
• Immediate seizure activity in all cases
• Severe hyperthermia resistant to antipyretics

Correct Answer: Nausea, vomiting, dizziness and CNS depression

Q30. Which monitoring parameter helps detect early agranulocytosis in patients on pyrazolone therapy?

• Serial platelet counts only
• Complete blood counts (particularly neutrophil count)
• Serum creatinine alone
• Fasting lipid profile monthly

Correct Answer: Complete blood counts (particularly neutrophil count)

Q31. Which statement about antipyrine’s protein binding is correct?

• It is highly protein-bound (>99%) and displaces many drugs
• It has moderate protein binding allowing tissue distribution
• It does not bind plasma proteins at all
• It binds exclusively to alpha-1-acid glycoprotein

Correct Answer: It has moderate protein binding allowing tissue distribution

Q32. Which factor most increases the risk of hepatic toxicity with antipyrine and related pyrazolones?

• Short-term single-dose use
• Chronic high-dose therapy and pre-existing liver disease
• Administration with antacids only
• Use only in topical formulations

Correct Answer: Chronic high-dose therapy and pre-existing liver disease

Q33. Which statement best describes antipyrine’s status in modern therapeutics?

• Widely used as first-line oral analgesic globally
• Less commonly used systemically due to safety concerns and alternatives; still used in some topical/diagnostic roles
• Used exclusively as an antibiotic today
• Completely banned worldwide with no clinical uses

Correct Answer: Less commonly used systemically due to safety concerns and alternatives; still used in some topical/diagnostic roles

Q34. In formulation science, antipyrine stability is particularly affected by:

• Exposure to strong oxidizing agents and high temperatures
• Complete protection from light only
• Exposure to neutral pH only with no other factors
• Presence of high concentrations of vitamin E

Correct Answer: Exposure to strong oxidizing agents and high temperatures

Q35. For a patient with hepatic enzyme induction (e.g., chronic rifampicin therapy), antipyrine dosing considerations would likely include:

• Reducing dose because induction decreases metabolism
• Potentially increasing dose due to increased metabolism and decreased plasma levels
• No change because antipyrine is not metabolized hepatically
• Switch to intravenous antipyrine to avoid induction

Correct Answer: Potentially increasing dose due to increased metabolism and decreased plasma levels

Q36. Which analytical method is commonly used to measure antipyrine plasma concentrations in pharmacokinetic studies?

• High-performance liquid chromatography (HPLC)
• Complete blood count
• Urine dipstick test only
• ELISA for antibodies

Correct Answer: High-performance liquid chromatography (HPLC)

Q37. A structural modification converting antipyrine into a more potent analgesic would most likely involve:

• Adding a bulky polar group that prevents CNS penetration
• Altering substitution on the pyrazolone ring to increase central COX inhibition
• Removing the pyrazolone core entirely
• Converting it into a peptide

Correct Answer: Altering substitution on the pyrazolone ring to increase central COX inhibition

Q38. Which adverse drug reaction is least expected with topical antipyrine- benzocaine ear drops?

• Local irritation or hypersensitivity
• Systemic agranulocytosis after single topical application
• Transient local numbness from benzocaine
• Occasional dizziness if absorbed systemically

Correct Answer: Systemic agranulocytosis after single topical application

Q39. The therapeutic index of antipyrine compared to many modern analgesics is generally considered to be:

• Wider and safer for long-term use
• Narrower, requiring careful dosing and monitoring
• Irrelevant because it is not absorbed systemically
• Infinite because it has no toxicity

Correct Answer: Narrower, requiring careful dosing and monitoring

Q40. Which lab test change would raise concern for hepatic injury during antipyrine therapy?

• Stable ALT/AST and rising hemoglobin
• Elevation of ALT and AST above normal limits
• Decrease in blood urea nitrogen only
• Elevated serum sodium only

Correct Answer: Elevation of ALT and AST above normal limits

Q41. In drug design, the pyrazolone scaffold is valued because it can provide:

• Selective adrenergic receptor agonism only
• Analgesic and antipyretic properties with tunable metabolic profiles
• Antiviral activity exclusively
• Permanent enzyme inhibition with no reversibility

Correct Answer: Analgesic and antipyretic properties with tunable metabolic profiles

Q42. Which clinical advice is appropriate for patients using topical antipyrine ear drops?

• Use continuously for months without monitoring
• Avoid use if tympanic membrane is perforated unless product is labeled for that use
• Ingest the drops orally if ear pain persists
• Mix with other otic medications without guidance

Correct Answer: Avoid use if tympanic membrane is perforated unless product is labeled for that use

Q43. Which is a classic实验 (experimental) use of antipyrine in pharmacology research rather than routine therapy?

• As a sedative-hypnotic challenge
• As a probe for assessing hepatic microsomal enzyme activity
• As an inhalational anesthetic
• As a bronchodilator in asthma studies

Correct Answer: As a probe for assessing hepatic microsomal enzyme activity

Q44. Pregnant patients should use antipyrine-containing products only with caution because:

• There is abundant evidence of teratogenicity at topical otic doses
• Systemic absorption may occur and safety in pregnancy is not well-established for some pyrazolones
• They cause hyperstimulation of the fetal heart directly
• They are completely safe and require no caution

Correct Answer: Systemic absorption may occur and safety in pregnancy is not well-established for some pyrazolones

Q45. Which is a pharmacokinetic parameter that often changes with age and affects antipyrine dosing?

• Pulmonary clearance only
• Hepatic metabolic capacity and half-life
• Ability to taste medications orally
• Color of the drug in solution

Correct Answer: Hepatic metabolic capacity and half-life

Q46. Which regulatory consideration has reduced the systemic use of pyrazolone analgesics including antipyrine?

• Proven universal efficacy over other NSAIDs
• Concerns over potentially severe hematologic and hepatic adverse effects
• Exclusively patent expiration issues
• Their inability to be formulated into tablets

Correct Answer: Concerns over potentially severe hematologic and hepatic adverse effects

Q47. Which counseling point is important when combining antipyrine with other analgesics like NSAIDs or acetaminophen?

• There is no risk of additive effects or toxicity
• Be cautious of additive analgesic/antipyretic effects and overlapping toxicities, especially hepatotoxicity or blood dyscrasias
• Antipyrine will neutralize the effect of other analgesics
• Always take all three together for best effect without consulting a clinician

Correct Answer: Be cautious of additive analgesic/antipyretic effects and overlapping toxicities, especially hepatotoxicity or blood dyscrasias

Q48. From a medicinal chemistry perspective, which change is least likely to improve antipyrine’s safety profile?

• Reducing metabolic bioactivation pathways that produce reactive intermediates
• Improving selectivity for central COX to reduce peripheral adverse effects
• Increasing formation of toxic metabolites via CYP activation
• Enhancing clearance to avoid accumulation

Correct Answer: Increasing formation of toxic metabolites via CYP activation

Q49. In a pharmacology exam, which mechanism would you cite for agranulocytosis caused by some pyrazolones?

• Iga-mediated immune complex deposition in bone marrow
• Immune-mediated destruction of neutrophils and/or direct toxic metabolites damaging bone marrow precursors
• Excessive stimulation of neutrophil production leading to exhaustion
• Increase in erythropoietin levels causing marrow suppression

Correct Answer: Immune-mediated destruction of neutrophils and/or direct toxic metabolites damaging bone marrow precursors

Q50. For objective assessment, which learning strategy best helps B. Pharm students master antipyrine pharmacology?

• Memorizing only trade names without mechanisms
• Combining mechanism-based study, clinical case discussions, PK calculations and MCQ practice
• Relying solely on lecture slides without active practice
• Studying unrelated drug classes only

Correct Answer: Combining mechanism-based study, clinical case discussions, PK calculations and MCQ practice

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