Thiothixene MCQs With Answer

Thiothixene MCQs With Answer is a focused study resource for B. Pharm students covering thiothixene — a high‑potency typical antipsychotic of the thioxanthene class. This introduction highlights key points including mechanism of action (D2 receptor antagonism), clinical uses in schizophrenia, common adverse effects (extrapyramidal symptoms, tardive dyskinesia), pharmacokinetics, monitoring and important drug interactions. These SEO‑rich, exam‑oriented MCQs emphasize pharmacology, therapeutic considerations, safety profiles and management of complications to strengthen retention and clinical reasoning. Ideal for revision before practicals and exams, the set balances basic concepts with deeper clinical and pharmaceutical details. Now let’s test your knowledge with 50 MCQs on this topic.

Q1. What is the primary mechanism of action of thiothixene?

• Selective serotonin reuptake inhibition
• D2 dopamine receptor antagonism
• NMDA receptor antagonism
• Monoamine oxidase inhibition

Correct Answer: D2 dopamine receptor antagonism

Q2. Thiothixene belongs to which chemical class of antipsychotics?

• Butyrophenones
• Thioxanthenes
• Phenothiazines
• Benzodiazepines

Correct Answer: Thioxanthenes

Q3. Which clinical indication is most appropriate for thiothixene?

• Acute bacterial meningitis
• Schizophrenia with predominant positive symptoms
• Major depressive disorder as monotherapy
• Generalized anxiety disorder first-line

Correct Answer: Schizophrenia with predominant positive symptoms

Q4. Compared to low‑potency typical antipsychotics, thiothixene is characterized by:

• Higher anticholinergic and antihistaminic effects
• Lower incidence of extrapyramidal symptoms
• Higher D2 receptor affinity and greater EPS risk
• No risk of tardive dyskinesia

Correct Answer: Higher D2 receptor affinity and greater EPS risk

Q5. Which adverse effect is most commonly associated with thiothixene?

• Severe hypoglycemia
• Extrapyramidal symptoms such as acute dystonia
• Renal failure as the primary toxicity
• Profound eosinophilia

Correct Answer: Extrapyramidal symptoms such as acute dystonia

Q6. The acute management of drug‑induced acute dystonia caused by thiothixene is:

• Administer intravenous naloxone
• Give intramuscular or intravenous anticholinergic such as benztropine or diphenhydramine
• Immediate dialysis
• Increase thiothixene dose

Correct Answer: Give intramuscular or intravenous anticholinergic such as benztropine or diphenhydramine

Q7. Which syndrome is a life‑threatening complication associated with high‑potency antipsychotics including thiothixene?

• Serotonin syndrome
• Neuroleptic malignant syndrome (NMS)
• Toxic epidermal necrolysis
• Stevens‑Johnson syndrome

Correct Answer: Neuroleptic malignant syndrome (NMS)

Q8. A cardinal feature of neuroleptic malignant syndrome includes:

• Hypotonia and hypothermia
• Hyperthermia, muscle rigidity, and autonomic instability
• Urticaria and angioedema
• Isolated hypertension without fever

Correct Answer: Hyperthermia, muscle rigidity, and autonomic instability

Q9. Which drug is commonly used in the treatment of severe NMS associated with thiothixene?

• Flumazenil
• Dantrolene
• Neostigmine
• Furosemide

Correct Answer: Dantrolene

Q10. Which receptor blockade contributes to orthostatic hypotension with thiothixene?

• Beta‑2 adrenergic receptor blockade
• Alpha‑1 adrenergic receptor blockade
• Muscarinic M2 receptor blockade
• GABA‑A receptor blockade

Correct Answer: Alpha‑1 adrenergic receptor blockade

Q11. Compared with atypical antipsychotics, thiothixene has a lower risk of:

• EPS
• Metabolic syndrome (weight gain, hyperglycemia, dyslipidemia)
• Cardiac arrhythmias
• Anticholinergic effects

Correct Answer: Metabolic syndrome (weight gain, hyperglycemia, dyslipidemia)

Q12. Which of the following monitoring parameters is most relevant for patients on thiothixene?

• Regular blood glucose monitoring only
• Periodic assessment for extrapyramidal signs and tardive dyskinesia
• No monitoring required once stable
• Daily measurement of serum creatinine

Correct Answer: Periodic assessment for extrapyramidal signs and tardive dyskinesia

Q13. Tardive dyskinesia associated with long‑term thiothixene use is best described as:

• Reversible within hours after stopping the drug
• An irreversible or persistent hyperkinetic movement disorder
• Exclusively a lower limb phenomenon
• Caused by cholinergic excess

Correct Answer: An irreversible or persistent hyperkinetic movement disorder

Q14. Which drug interaction increases the risk of extrapyramidal effects when combined with thiothixene?

• Concurrent use of metoclopramide
• Concurrent use of vitamin C
• Concurrent use of acetaminophen
• Concurrent use of oral contraceptives only

Correct Answer: Concurrent use of metoclopramide

Q15. The sedative properties of thiothixene are primarily due to blockade of which receptor?

• Histamine H1 receptor
• NMDA receptor
• Dopamine D3 receptor only
• Glycine receptor

Correct Answer: Histamine H1 receptor

Q16. Which formulation is thiothixene commonly available as for oral administration?

• Immediate‑release oral tablets
• Subcutaneous implant only
• Inhalation powder
• Transdermal patch

Correct Answer: Immediate‑release oral tablets

Q17. When initiating thiothixene therapy, which warning is most important for elderly patients with dementia‑related psychosis?

• Increased risk of stroke and mortality
• No specific warnings; it’s safer in elderly
• Guaranteed improvement in cognition
• It prevents aspiration pneumonia

Correct Answer: Increased risk of stroke and mortality

Q18. Which of the following statements about thiothixene metabolism is correct?

• It is primarily eliminated unchanged in urine
• It undergoes hepatic metabolism and biotransformation
• It is exhaled unchanged through the lungs
• It is converted into an active opioid metabolite

Correct Answer: It undergoes hepatic metabolism and biotransformation

Q19. Which laboratory test may be considered before and during long‑term thiothixene therapy?

• Complete blood count (CBC) to monitor for rare blood dyscrasias
• Frequent blood cultures
• Urine drug screen for THC only
• Serum amylase every week

Correct Answer: Complete blood count (CBC) to monitor for rare blood dyscrasias

Q20. The risk of QT prolongation with thiothixene requires caution when co‑administered with:

• Antacids
• Other QT‑prolonging drugs such as certain antiarrhythmics
• Topical emollients
• Oral iron supplements only

Correct Answer: Other QT‑prolonging drugs such as certain antiarrhythmics

Q21. Which symptom suggests akathisia in a patient treated with thiothixene?

• Severe bradycardia
• Inner restlessness and constant need to move
• Auditory hallucinations only
• Marked constipation

Correct Answer: Inner restlessness and constant need to move

Q22. Preferred management for akathisia induced by thiothixene includes:

• High‑dose dopamine agonists without caution
• Beta‑blockers (e.g., propranolol) or benzodiazepines
• Immediate ECT only
• Increase antipsychotic dose

Correct Answer: Beta‑blockers (e.g., propranolol) or benzodiazepines

Q23. Which of the following is a contraindication to thiothixene therapy?

• Comatose state or severe central nervous system depression
• Mild seasonal allergies
• Stable hypothyroidism on replacement therapy
• Controlled hypertension on ACE inhibitor

Correct Answer: Comatose state or severe central nervous system depression

Q24. Which neurotransmitter system is primarily implicated in the therapeutic effect of thiothixene on positive psychotic symptoms?

• Serotonergic 5‑HT2A blockade only
• Mesolimbic dopamine pathway D2 antagonism
• GABAergic enhancement
• Cholinergic potentiation

Correct Answer: Mesolimbic dopamine pathway D2 antagonism

Q25. Which adverse effect is less prominent with high‑potency agents like thiothixene compared with low‑potency phenothiazines?

• Extrapyramidal symptoms
• Anticholinergic and significant sedation
• Tardive dyskinesia
• Prolactin elevation

Correct Answer: Anticholinergic and significant sedation

Q26. Thiothixene’s antagonism at which receptor can lead to elevated prolactin levels?

• Alpha‑2 adrenergic receptor
• Dopamine D2 receptor
• Serotonin 5‑HT1A receptor
• GABA‑B receptor

Correct Answer: Dopamine D2 receptor

Q27. Which counseling point should a pharmacist give to a patient starting thiothixene?

• Expect immediate cure of all symptoms within hours
• Avoid abrupt discontinuation and report muscle stiffness, fever or uncontrolled movements
• Use extra vitamin D to prevent EPS
• Stop all other medications without consulting a doctor

Correct Answer: Avoid abrupt discontinuation and report muscle stiffness, fever or uncontrolled movements

Q28. Co‑administration of thiothixene with central nervous system depressants may cause:

• Reduced sedation
• Enhanced sedation and respiratory depression
• Immediate hepatoprotection
• Prevention of extrapyramidal symptoms

Correct Answer: Enhanced sedation and respiratory depression

Q29. Which pharmacological property explains why thiothixene can cause anticholinergic side effects, albeit less than low‑potency agents?

• Strong inhibition of monoamine oxidase
• Some antagonism at muscarinic acetylcholine receptors
• Direct agonism at muscarinic receptors
• Inhibition of acetylcholinesterase

Correct Answer: Some antagonism at muscarinic acetylcholine receptors

Q30. In cases of thiothixene overdose, which immediate supportive measure is most appropriate?

• Maintain airway, breathing and circulation, and provide supportive care
• Administer high‑dose insulin immediately
• Give large doses of naloxone
• Immediate whole bowel irrigation only

Correct Answer: Maintain airway, breathing and circulation, and provide supportive care

Q31. Which movement disorder is characterized by sustained muscle contractions causing twisting and repetitive movements and may occur with thiothixene?

• Acute dystonia
• Neuroleptic malignant syndrome
• Tardive dyskinesia only
• Myasthenia gravis

Correct Answer: Acute dystonia

Q32. Which class of drugs may reduce the antipsychotic efficacy of thiothixene by inducing hepatic enzymes?

• CYP450 enzyme inducers (e.g., carbamazepine, rifampicin)
• Proton pump inhibitors
• Topical steroids
• Non‑steroidal anti‑inflammatories only

Correct Answer: CYP450 enzyme inducers (e.g., carbamazepine, rifampicin)

Q33. Which physical sign is an early indicator of parkinsonism from thiothixene?

• Cogwheel rigidity and bradykinesia
• Hyperreflexia and spasticity
• Severe diarrhea
• Blindness

Correct Answer: Cogwheel rigidity and bradykinesia

Q34. For pharmacology exam, which statement best describes thiothixene’s potency?

• Thiothixene is a low‑potency antipsychotic
• Thiothixene is a high‑potency typical antipsychotic with strong D2 blockade
• Thiothixene is primarily an anxiolytic
• Thiothixene acts as a selective serotonin reuptake enhancer

Correct Answer: Thiothixene is a high‑potency typical antipsychotic with strong D2 blockade

Q35. Which adverse endocrine effect can occur due to dopamine blockade by thiothixene?

• Hypoprolactinemia
• Hyperprolactinemia leading to galactorrhea and menstrual disturbances
• Decreased thyroid hormone production directly
• Hyperaldosteronism

Correct Answer: Hyperprolactinemia leading to galactorrhea and menstrual disturbances

Q36. If a patient on thiothixene develops severe anticholinergic effects, which symptomatic treatment is appropriate?

• Administer physostigmine under controlled conditions
• Give high‑dose atropine
• Increase thiothixene dose
• Immediate ECT

Correct Answer: Administer physostigmine under controlled conditions

Q37. Which neurotransmitter imbalance theory explains the emergence of extrapyramidal side effects with thiothixene?

• Excess serotonergic transmission in nigrostriatal pathway
• Excess dopamine in nigrostriatal pathway
• Dopamine blockade in the nigrostriatal pathway leading to cholinergic–dopaminergic imbalance
• Only GABAergic dysfunction

Correct Answer: Dopamine blockade in the nigrostriatal pathway leading to cholinergic–dopaminergic imbalance

Q38. Which symptom complex differentiates acute dystonia from akathisia?

• Acute dystonia presents as inner restlessness; akathisia causes sustained spasms
• Acute dystonia involves sustained muscle contractions and abnormal postures; akathisia is subjective restlessness with motor agitation
• Both are identical in presentation
• Akathisia involves fever and rigidity

Correct Answer: Acute dystonia involves sustained muscle contractions and abnormal postures; akathisia is subjective restlessness with motor agitation

Q39. Which antipsychotic property increases risk of sedation and weight gain more than thiothixene?

• High D2 antagonism only
• Strong antihistaminic (H1) and 5‑HT2C blockade typical of some atypicals
• Pure alpha‑2 agonism
• High potency anti‑serotonergic effect only

Correct Answer: Strong antihistaminic (H1) and 5‑HT2C blockade typical of some atypicals

Q40. Which patient history detail would prompt extra caution before prescribing thiothixene?

• History of controlled seasonal allergies
• History of Parkinson’s disease or Parkinsonian symptoms
• Minor resolved childhood ear infection
• Remote appendectomy without complications

Correct Answer: History of Parkinson’s disease or Parkinsonian symptoms

Q41. Which of the following is true about thiothixene and breastfeeding?

• Thiothixene is safe and does not pass into breast milk
• Thiothixene can be excreted in breast milk; caution and specialist advice are recommended
• Thiothixene enhances milk production and is recommended
• Thiothixene completely prevents lactation

Correct Answer: Thiothixene can be excreted in breast milk; caution and specialist advice are recommended

Q42. Which agent can be used prophylactically to reduce acute dystonic reactions when starting high‑potency antipsychotics?

• Daily benzodiazepine prophylaxis indefinitely
• Short‑term anticholinergic (e.g., benztropine) at initiation if high risk
• High‑dose opioid therapy
• Oral iron supplementation

Correct Answer: Short‑term anticholinergic (e.g., benztropine) at initiation if high risk

Q43. Which pharmacokinetic characteristic best describes thiothixene?

• Rapid renal excretion with minimal metabolism
• Hepatic metabolism with variable half‑life influenced by hepatic function
• Fully bioactivated by gut flora only
• Exclusively cleared by pulmonary excretion

Correct Answer: Hepatic metabolism with variable half‑life influenced by hepatic function

Q44. Which statement about switching from thiothixene to an atypical antipsychotic is TRUE?

• No monitoring is required during the switch
• Gradual cross‑tapering with monitoring for withdrawal symptoms and EPS is recommended
• Thiothixene must be stopped abruptly before starting any atypical
• Switching is contraindicated in all cases

Correct Answer: Gradual cross‑tapering with monitoring for withdrawal symptoms and EPS is recommended

Q45. Which of the following is a pharmacovigilance concern specifically related to long‑term thiothixene therapy?

• Development of chronic cough
• Emergence of tardive dyskinesia and persistent movement disorders
• Frequent spontaneous bone fractures within days
• Immediate renal tubular necrosis in all patients

Correct Answer: Emergence of tardive dyskinesia and persistent movement disorders

Q46. Which symptom would suggest an anticholinergic adverse effect from thiothixene?

• Excessive salivation and diarrhea
• Dry mouth, blurred vision and urinary retention
• Brisk tendon reflexes
• Profuse sweating and rhinorrhea

Correct Answer: Dry mouth, blurred vision and urinary retention

Q47. In the event of severe orthostatic hypotension due to thiothixene, an initial management step is:

• Immediate bolus of thiothixene
• Assess fluid status, advise slow position changes, and consider dose reduction
• Encourage rapid standing after lying down
• Administer high‑dose beta‑agonists

Correct Answer: Assess fluid status, advise slow position changes, and consider dose reduction

Q48. Which class of medications may worsen anticholinergic side effects when combined with thiothixene?

• Cholinesterase inhibitors
• Other anticholinergic agents such as oxybutynin or tricyclic antidepressants
• Topical antihistamines only
• Insulin

Correct Answer: Other anticholinergic agents such as oxybutynin or tricyclic antidepressants

Q49. For exam purposes: which statement best summarizes thiothixene’s therapeutic focus?

• Primarily used for mood stabilization in bipolar depression
• Used mainly to treat positive symptoms of psychosis as a typical antipsychotic
• First‑line therapy for obsessive‑compulsive disorder
• Predominantly an antihypertensive agent

Correct Answer: Used mainly to treat positive symptoms of psychosis as a typical antipsychotic

Q50. Which practical pharmacy consideration is important when dispensing thiothixene?

• No counseling is necessary for antipsychotics
• Advise patients about potential EPS, the need for adherence, and when to seek urgent care for fever or rigidity
• Tell patients they can double doses if they miss one day
• Recommend immediate cessation if mild restlessness occurs

Correct Answer: Advise patients about potential EPS, the need for adherence, and when to seek urgent care for fever or rigidity

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