Flurobuterophenones – Droperidol MCQs With Answer
Flurobuterophenones (commonly written as fluorobutyrophenones) include droperidol, a butyrophenone-class antipsychotic and antiemetic widely covered in B.Pharm curricula. This introduction reviews key points: chemical class, structure–activity relationships, D2 receptor antagonism, antiemetic and sedative uses, pharmacokinetics (rapid IV onset, hepatic metabolism, short half‑life), major adverse effects (extrapyramidal symptoms, QT prolongation, hypotension), drug interactions, and monitoring. Understanding these concepts helps in formulation, dosing, safety screening, and therapeutic decision-making. Keywords: Flurobuterophenones, droperidol, butyrophenone, D2 antagonism, pharmacokinetics, adverse effects, QT prolongation, B.Pharm. Now let’s test your knowledge with 50 MCQs on this topic.
Q1. What chemical class does droperidol belong to?
- Phenothiazines
- Butyrophenones
- Benzodiazepines
- Barbiturates
Correct Answer: Butyrophenones
Q2. The term “Flurobuterophenones” in the context of droperidol most closely refers to:
- A specific manufacturing impurity
- A class of molecules with a butyrophenone core and halogen substituents
- An unrelated opioid subclass
- A brand name formulation
Correct Answer: A class of molecules with a butyrophenone core and halogen substituents
Q3. The primary pharmacological mechanism of droperidol is:
- GABA-A receptor agonism
- Norepinephrine reuptake inhibition
- Dopamine D2 receptor antagonism
- Serotonin 5-HT3 receptor agonism
Correct Answer: Dopamine D2 receptor antagonism
Q4. Which clinical use is droperidol most commonly associated with in perioperative care?
- Preoperative anxiolysis via oral route
- Prophylaxis of postoperative nausea and vomiting (PONV)
- Long-term maintenance therapy for schizophrenia
- Chronic pain management
Correct Answer: Prophylaxis of postoperative nausea and vomiting (PONV)
Q5. A key safety concern that led to regulatory warnings for droperidol is:
- Renal toxicity with single doses
- Severe hyperglycemia
- QT interval prolongation and risk of torsades de pointes
- High risk of drug dependence
Correct Answer: QT interval prolongation and risk of torsades de pointes
Q6. Typical intravenous antiemetic dosing of droperidol for PONV in adults is closest to:
- 0.01–0.05 mg
- 0.625–1.25 mg
- 10–20 mg
- 50–100 mg
Correct Answer: 0.625–1.25 mg
Q7. Which organ system is primarily responsible for the metabolism of droperidol?
- Kidneys
- Lungs
- Liver
- Skin
Correct Answer: Liver
Q8. Which adverse effect is characteristic of D2 receptor blockade and can occur with droperidol?
- Bronchospasm
- Extrapyramidal symptoms (EPS)
- Hyperkalemia
- Neutropenia
Correct Answer: Extrapyramidal symptoms (EPS)
Q9. Droperidol’s onset of action after intravenous administration is typically:
- Several hours
- Within minutes
- 24–48 hours
- Unpredictable and very delayed
Correct Answer: Within minutes
Q10. Which monitoring is recommended when giving droperidol IV in patients at risk for QT prolongation?
- Blood glucose monitoring only
- No monitoring required
- Electrocardiogram (ECG) monitoring
- Pulmonary function testing
Correct Answer: Electrocardiogram (ECG) monitoring
Q11. An important drug interaction with droperidol that increases QT risk is co-administration with:
- Aspirin
- Other QT-prolonging agents such as certain antiarrhythmics or macrolides
- Insulin
- Topical corticosteroids
Correct Answer: Other QT-prolonging agents such as certain antiarrhythmics or macrolides
Q12. Which patient population should be treated with caution or avoided for droperidol due to sensitivity to dopamine blockade?
- Patients with Parkinson’s disease
- Patients with hypothyroidism
- Patients with hyperlipidemia
- Patients with asthma
Correct Answer: Patients with Parkinson’s disease
Q13. The term structure–activity relationship (SAR) for flurobuterophenones typically studies:
- How chemical substitutions affect color
- How substitutions on the butyrophenone core affect pharmacologic potency and selectivity
- Only the melting point of the compound
- How to manufacture tablets cheaply
Correct Answer: How substitutions on the butyrophenone core affect pharmacologic potency and selectivity
Q14. Which adverse drug reaction is a rare but life‑threatening complication of antipsychotics including droperidol?
- Neuroleptic malignant syndrome (NMS)
- Acute appendicitis
- Myocardial infarction within minutes of dosing
- Immediate anaphylactic shock in all patients
Correct Answer: Neuroleptic malignant syndrome (NMS)
Q15. Droperidol’s elimination half‑life is best described as:
- Extremely long (>72 hours)
- Very short (minutes only)
- Short to moderate (around 2–4 hours)
- Indefinite and accumulative
Correct Answer: Short to moderate (around 2–4 hours)
Q16. A structural feature often present in fluorobutyrophenones that increases lipophilicity and potency is:
- A large carbohydrate side chain
- A para-halogen (e.g., fluorine) substitution on an aromatic ring
- An attached peptide sequence
- A charged quaternary ammonium group
Correct Answer: A para-halogen (e.g., fluorine) substitution on an aromatic ring
Q17. Which formulation routes are commonly available for droperidol in clinical practice?
- Oral tablets only
- Intravenous and intramuscular injections
- Topical cream
- Transdermal patch
Correct Answer: Intravenous and intramuscular injections
Q18. In patients with hepatic impairment, droperidol dosing should be:
- Unchanged since it’s renally cleared only
- Used with caution and dose adjustment may be necessary
- Increased to overcome decreased clearance
- Given as a continuous high-dose infusion
Correct Answer: Used with caution and dose adjustment may be necessary
Q19. Which receptor blockade besides D2 is responsible for droperidol-associated hypotension?
- Beta-2 adrenergic agonism
- Alpha-1 adrenergic blockade
- Muscarinic M3 activation
- Glycine receptor antagonism
Correct Answer: Alpha-1 adrenergic blockade
Q20. For B.Pharm students studying droperidol, which analytical method is commonly used to quantify plasma concentrations in pharmacokinetic studies?
- UV-visible spectroscopy without extraction
- High-performance liquid chromatography (HPLC) with appropriate detection
- Simple pH paper test
- Gram staining
Correct Answer: High-performance liquid chromatography (HPLC) with appropriate detection
Q21. Which side effect may be managed acutely using anticholinergic agents like benztropine when caused by droperidol?
- Tardive dyskinesia
- Acute dystonic reactions
- QT prolongation
- Hypotension unresponsive to fluids
Correct Answer: Acute dystonic reactions
Q22. Which patient history element increases the risk of droperidol-induced torsades de pointes?
- History of peptic ulcer disease
- Family history of long QT syndrome
- Prior cholecystectomy
- Seasonal allergies
Correct Answer: Family history of long QT syndrome
Q23. In the context of drug development, modifying butyrophenone scaffolds with electron-withdrawing groups like fluorine generally:
- Decreases central nervous system penetration
- Increases lipophilicity and often enhances CNS potency
- Eliminates pharmacologic activity entirely
- Converts the drug into a peptide
Correct Answer: Increases lipophilicity and often enhances CNS potency
Q24. Which laboratory parameter is most directly relevant to assess a patient at risk before administering droperidol?
- Liver function tests and baseline ECG
- Serum amylase only
- Fasting lipid profile
- Serum magnesium only if symptomatic
Correct Answer: Liver function tests and baseline ECG
Q25. Droperidol can antagonize which antiemetic receptor to reduce nausea?
- Histamine H1 receptor
- Serotonin 5-HT3 receptor
- Dopamine D2 receptor in the chemoreceptor trigger zone
- Opioid mu receptor
Correct Answer: Dopamine D2 receptor in the chemoreceptor trigger zone
Q26. The phenomenon of tardive dyskinesia associated with chronic dopamine blockade is characterized by:
- Acute bronchospasm
- Irreversible involuntary, repetitive movements often of the face and tongue
- Rapid improvement after single dose
- Severe hypotension only
Correct Answer: Irreversible involuntary, repetitive movements often of the face and tongue
Q27. A pharmacokinetic property that influences droperidol’s quick clinical effect after IV dosing is:
- High plasma protein binding prevents CNS access
- Rapid distribution to brain due to lipophilicity
- Delayed absorption from the stomach
- Extensive renal reabsorption
Correct Answer: Rapid distribution to brain due to lipophilicity
Q28. Which of the following is an appropriate immediate management step for suspected droperidol-induced torsades de pointes?
- Administer IV magnesium sulfate and cardioversion if unstable
- Give oral antiemetic immediately
- Start long-term beta blocker therapy
- Administer high-dose insulin
Correct Answer: Administer IV magnesium sulfate and cardioversion if unstable
Q29. Which statement about droperidol and pregnancy is most appropriate for B.Pharm counselling?
- Droperidol is absolutely safe in all trimesters
- Use in pregnancy requires risk–benefit assessment and avoidance if unnecessary
- It is a recommended routine therapy for morning sickness
- Droperidol is an essential vitamin supplement
Correct Answer: Use in pregnancy requires risk–benefit assessment and avoidance if unnecessary
Q30. The term “butyrophenone” refers to which aspect of the molecule?
- Presence of a benzodiazepine ring
- A phenyl ring attached to a butanone (butyro) backbone
- A sugar moiety
- An esterified fatty acid
Correct Answer: A phenyl ring attached to a butanone (butyro) backbone
Q31. When combining droperidol with opioids during anesthesia, pharmacists should be aware that:
- The combination always eliminates QT risk
- Combined CNS depressant effects may increase sedation and respiratory depression
- Opioids neutralize droperidol’s antiemetic action
- There are no interactions of clinical relevance
Correct Answer: Combined CNS depressant effects may increase sedation and respiratory depression
Q32. Which adverse effect is more likely with higher doses of droperidol used for sedation compared with low antiemetic doses?
- Increased extrapyramidal symptoms and hypotension
- Improved renal function
- Reduced sedation
- Immediate hair growth
Correct Answer: Increased extrapyramidal symptoms and hypotension
Q33. In drug stability and compounding for parenteral use, droperidol solutions should be stored how?
- Exposed to direct sunlight at room temperature
- According to manufacturer guidance, typically protected from light and refrigerated if required
- Frozen and thawed repeatedly
- Mixed with alkaline solutions to increase potency
Correct Answer: According to manufacturer guidance, typically protected from light and refrigerated if required
Q34. Which pharmacodynamic effect explains droperidol’s antiemetic action in the chemoreceptor trigger zone (CTZ)?
- 5-HT3 receptor activation in the GI tract
- D2 receptor blockade in the CTZ
- NMDA receptor agonism
- Activation of histamine H2 receptors
Correct Answer: D2 receptor blockade in the CTZ
Q35. Which regulatory action affected droperidol’s use in some countries due to cardiac safety concerns?
- Complete over-the-counter availability
- Black box warnings or restricted use recommendations related to QT prolongation
- Mandatory co-prescription with benzodiazepines
- Ban on intravenous formulations only
Correct Answer: Black box warnings or restricted use recommendations related to QT prolongation
Q36. Droperidol’s effect on prolactin levels is an example of which pharmacological consequence?
- Decreased insulin release
- Dopamine blockade leading to hyperprolactinemia
- Increased thyroid hormone activation
- Direct adrenal stimulation
Correct Answer: Dopamine blockade leading to hyperprolactinemia
Q37. For forensic or analytical purposes, which sample matrix is commonly used to detect droperidol post-administration?
- Hair samples only
- Plasma or urine samples
- Nail clippings exclusively
- Saliva cannot be used
Correct Answer: Plasma or urine samples
Q38. Which descriptor best characterizes droperidol’s receptor binding profile relevant to its clinical effects?
- Selective serotonin reuptake inhibition
- Predominant D2 antagonism with some alpha-adrenergic blockade
- Full opioid receptor agonist
- Pure muscarinic agonist
Correct Answer: Predominant D2 antagonism with some alpha-adrenergic blockade
Q39. If a patient develops acute dystonia after droperidol, the fastest symptomatic treatment is:
- Oral NSAIDs
- Intravenous or intramuscular anticholinergic like benztropine or diphenhydramine
- High-dose oral vitamin C
- Topical anesthetic
Correct Answer: Intravenous or intramuscular anticholinergic like benztropine or diphenhydramine
Q40. Which characteristic of droperidol contributes to its use as a short‑acting perioperative agent?
- Extremely long tissue retention
- Rapid onset and relatively short duration of action
- Permanent receptor binding
- Lack of central nervous system penetration
Correct Answer: Rapid onset and relatively short duration of action
Q41. Which symptom is most indicative of anticholinergic toxicity rather than droperidol-induced EPS?
- Severe facial grimacing and tongue protrusion
- Dry mouth, blurred vision, urinary retention, and hyperthermia
- Prominent bradykinesia only
- Profound hypotension without other signs
Correct Answer: Dry mouth, blurred vision, urinary retention, and hyperthermia
Q42. In structure–activity relationship (SAR) studies of butyrophenones, removing a bulky lipophilic substituent typically:
- Increases CNS potency dramatically
- May reduce blood–brain barrier penetration and decrease potency
- Converts molecule into an antibiotic
- Has no effect on pharmacology
Correct Answer: May reduce blood–brain barrier penetration and decrease potency
Q43. Which feature distinguishes droperidol from typical benzodiazepines in clinical use?
- Droperidol is primarily an antipsychotic/antiemetic with dopamine antagonism; benzodiazepines act via GABA-A facilitation
- Droperidol is a GABA-A agonist while benzodiazepines antagonize dopamine
- Both drug classes are chemically identical
- Benzodiazepines cause QT prolongation, droperidol does not
Correct Answer: Droperidol is primarily an antipsychotic/antiemetic with dopamine antagonism; benzodiazepines act via GABA-A facilitation
Q44. When teaching formulation considerations, B.Pharm students should note that droperidol parenteral products must be free from:
- Pyrogens and particulate matter
- Any sodium content
- All preservatives
- Lipophilic solvents always present
Correct Answer: Pyrogens and particulate matter
Q45. Which clinical sign would most likely prompt discontinuation of droperidol and urgent evaluation?
- Mild dry mouth after a single dose
- Onset of syncope, palpitations, or documented polymorphic ventricular tachycardia
- Transient mild sedation
- Temporary mild nausea
Correct Answer: Onset of syncope, palpitations, or documented polymorphic ventricular tachycardia
Q46. For pharmacology exams, a reliable mnemonic to remember droperidol’s main effects would emphasize:
- Anticholinergic, insulinotropic, prokinetic
- Dopamine D2 blockade (antiemetic/antipsychotic), alpha-1 blockade (hypotension), QT risk
- Pure opioid-like analgesia only
- Direct antiviral activity
Correct Answer: Dopamine D2 blockade (antiemetic/antipsychotic), alpha-1 blockade (hypotension), QT risk
Q47. Which clinical scenario is a relative contraindication to droperidol use?
- Well-controlled hypertension on a single ACE inhibitor
- History of prolonged QT interval or torsades de pointes
- Seasonal allergic rhinitis
- Noncomplicated controlled diabetes mellitus
Correct Answer: History of prolonged QT interval or torsades de pointes
Q48. In overdose, droperidol toxicity management focuses on:
- Supportive care, airway/ventilation, managing hypotension, treating arrhythmias
- Immediate gastric lavage only without supportive care
- Administering oral activated charcoal after 48 hours
- Rapid infusion of glucose and potassium only
Correct Answer: Supportive care, airway/ventilation, managing hypotension, treating arrhythmias
Q49. From a medicinal chemistry perspective, introducing a fluorine atom into butyrophenones often affects:
- Stability, lipophilicity, and sometimes receptor binding affinity
- Color of the compound only
- The ability to form ionic salts exclusively
- Conversion into a peptide bond
Correct Answer: Stability, lipophilicity, and sometimes receptor binding affinity
Q50. For B.Pharm students preparing for exams, the most important practical counseling point for droperidol used perioperatively is:
- It causes instant immune tolerance
- Inform about potential sedation, blood pressure effects, and rare cardiac arrhythmia risk; monitor appropriately
- Recommend it for routine outpatient use without monitoring
- Advise patients it will permanently cure motion sickness
Correct Answer: Inform about potential sedation, blood pressure effects, and rare cardiac arrhythmia risk; monitor appropriately

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.
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