Dexamethasone MCQs With Answer

Dexamethasone MCQs With Answer is a concise, focused resource designed for B. Pharm students to master dexamethasone pharmacology, therapeutics, and safety. This introduction highlights key concepts: mechanism of action as a glucocorticoid, pharmacokinetics such as long half‑life and CYP3A4 metabolism, major clinical indications (anti‑inflammatory, cerebral edema, antiemetic, neonatal lung maturation), adverse effects, dosing strategies, formulations, monitoring, and important drug interactions. These keyword‑rich points prepare students for exam‑style questions and practical dispensing decisions. Clear, clinically relevant MCQs will reinforce learning and improve application of theoretical knowledge in pharmacy practice. Now let’s test your knowledge with 30 MCQs on this topic.

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

• Inhibition of cyclooxygenase-1 enzyme
• Activation of mineralocorticoid receptors to retain sodium
• Binding to glucocorticoid receptors and modulation of gene transcription
• Blockade of histamine H1 receptors

Correct Answer: Binding to glucocorticoid receptors and modulation of gene transcription

Q2. Compared with prednisone, dexamethasone is best described as:

• Less potent and shorter acting
• More potent and longer acting
• Equal potency but more mineralocorticoid activity
• Only active when given orally

Correct Answer: More potent and longer acting

Q3. Which enzyme primarily metabolizes dexamethasone?

• CYP2D6
• CYP3A4
• Monoamine oxidase
• Alcohol dehydrogenase

Correct Answer: CYP3A4

Q4. A major antiemetic use of dexamethasone is in combination therapy for:

• Acute gastroenteritis in children
• Postoperative nausea unrelated to chemotherapy
• Chemotherapy-induced nausea and vomiting
• Motion sickness

Correct Answer: Chemotherapy-induced nausea and vomiting

Q5. Which formulation of dexamethasone is commonly used for rapid intravenous administration in emergencies?

• Dexamethasone oral tablets
• Dexamethasone sodium phosphate injection
• Dexamethasone acetate depot suspension
• Topical dexamethasone cream

Correct Answer: Dexamethasone sodium phosphate injection

Q6. Which adverse effect is most characteristic of long-term systemic dexamethasone therapy?

• Hypoglycemia
• Adrenal suppression and Cushingoid features
• Hyperprolactinemia
• Hemolytic anemia

Correct Answer: Adrenal suppression and Cushingoid features

Q7. Dexamethasone is indicated for reducing intracranial pressure in cases of:

• Acute ischemic stroke within 4.5 hours
• Cerebral edema due to brain tumors
• Bacterial meningitis as monotherapy
• Simple febrile seizures

Correct Answer: Cerebral edema due to brain tumors

Q8. The relative anti-inflammatory potency of dexamethasone compared to hydrocortisone is approximately:

• Equal
• About 25 times greater
• About half as potent
• 100 times greater

Correct Answer: About 25 times greater

Q9. Which pharmacokinetic feature best describes dexamethasone?

• Extensive first-pass metabolism with very low oral bioavailability
• Short biological half-life requiring multiple daily doses
• Long biological half-life allowing once-daily dosing
• Excreted unchanged in urine predominantly

Correct Answer: Long biological half-life allowing once-daily dosing

Q10. When tapering long-term dexamethasone therapy, the main concern is:

• Rebound hypertension
• Additive sedation
• Adrenal insufficiency due to suppressed HPA axis
• Permanent hypokalemia

Correct Answer: Adrenal insufficiency due to suppressed HPA axis

Q11. In pregnant women at risk of preterm delivery, dexamethasone is used to:

• Induce labor within 24 hours
• Promote fetal lung maturation
• Prevent maternal gestational diabetes
• Reduce maternal blood pressure

Correct Answer: Promote fetal lung maturation

Q12. Dexamethasone’s mineralocorticoid activity compared to aldosterone is:

• Very high, causing marked sodium retention
• Moderate and dose-dependent
• Minimal to negligible
• Equal to cortisol

Correct Answer: Minimal to negligible

Q13. Which laboratory parameter should be monitored during high‑dose dexamethasone therapy?

• Serum creatine kinase only
• Fasting blood glucose and electrolytes
• Serum lipase exclusively
• Thyroid-stimulating hormone only

Correct Answer: Fasting blood glucose and electrolytes

Q14. A significant drug interaction is expected when dexamethasone is coadministered with a strong CYP3A4 inhibitor because it will:

• Decrease dexamethasone plasma levels
• Increase dexamethasone plasma levels and risk toxicity
• Convert dexamethasone into an inactive metabolite
• Prevent dexamethasone absorption from the gut

Correct Answer: Increase dexamethasone plasma levels and risk toxicity

Q15. In neonatal care, a single course of maternal antenatal dexamethasone reduces the incidence of:

• Neonatal hypothermia
• Respiratory distress syndrome
• Neonatal sepsis
• Congenital heart defects

Correct Answer: Respiratory distress syndrome

Q16. Which statement about topical vs systemic dexamethasone is correct?

• Topical dexamethasone provides identical systemic effects as oral doses
• Systemic dexamethasone is preferred for generalized autoimmune disease
• Topical use is recommended for systemic infections
• Systemic dexamethasone has no risk of systemic adverse effects

Correct Answer: Systemic dexamethasone is preferred for generalized autoimmune disease

Q17. An important contraindication to systemic dexamethasone is:

• Active uncontrolled systemic fungal infection
• Mild allergic rhinitis
• Controlled hypothyroidism
• Well-managed hypertension

Correct Answer: Active uncontrolled systemic fungal infection

Q18. Which dosing strategy is correct for using dexamethasone as a single perioperative antiemetic dose?

• High-dose continuous infusion for 48 hours
• Single intravenous dose given at induction of anesthesia
• Topical application to the surgical site
• Oral tapering starting one week pre-op

Correct Answer: Single intravenous dose given at induction of anesthesia

Q19. The genomic effects of dexamethasone primarily involve:

• Rapid membrane ion channel modulation within seconds
• Direct enzymatic inhibition of COX-2 only
• Alteration of transcription of anti-inflammatory and pro-inflammatory genes
• Immediate vasodilation via nitric oxide release

Correct Answer: Alteration of transcription of anti-inflammatory and pro-inflammatory genes

Q20. A pharmacist preparing an intramuscular depot of dexamethasone should know that acetate formulations are typically:

• More water-soluble and rapidly absorbed
• Less soluble and longer acting than phosphate salts
• Intended for IV bolus only
• Equally soluble as the sodium phosphate salt

Correct Answer: Less soluble and longer acting than phosphate salts

Q21. Which clinical use of dexamethasone was supported during the COVID-19 pandemic?

• Treatment for mild, asymptomatic COVID-19 cases
• Reduction in mortality for hospitalized patients requiring oxygen or mechanical ventilation
• Prevention of SARS-CoV-2 infection in exposed individuals
• Antiviral eradication of the virus

Correct Answer: Reduction in mortality for hospitalized patients requiring oxygen or mechanical ventilation

Q22. Dexamethasone can cause which effect on bone with long-term use?

• Increased bone density
• Osteoporosis and increased fracture risk
• Enhanced calcium absorption from the gut
• Stimulated osteoblast activity exclusively

Correct Answer: Osteoporosis and increased fracture risk

Q23. When converting prednisolone to dexamethasone equivalent dose, you should expect dexamethasone dose to be:

• Approximately 5–7 times lower than prednisolone by mg
• Approximately 10 times higher in mg than prednisolone
• Identical in mg to prednisolone
• Completely non-equivalent due to different receptors

Correct Answer: Approximately 5–7 times lower than prednisolone by mg

Q24. In assessing an adverse psychiatric reaction to dexamethasone, which symptom is commonly observed?

• Depressive symptoms, mood swings, or psychosis
• Rapid improvement of chronic schizophrenia
• Permanent amnesia after a single dose
• Selective enhancement of cognitive function

Correct Answer: Depressive symptoms, mood swings, or psychosis

Q25. For patients with diabetes, dexamethasone therapy most likely requires:

• No change to glucose monitoring or therapy
• Decreased glucose monitoring due to hypoglycemic risk
• Closer blood glucose monitoring and possible adjustment of antidiabetic therapy
• Immediate cessation of all antidiabetic medications

Correct Answer: Closer blood glucose monitoring and possible adjustment of antidiabetic therapy

Q26. Which statement about withdrawal from high-dose dexamethasone is accurate?

• Sudden discontinuation is safe after any duration
• Tapering is recommended to allow HPA axis recovery after prolonged therapy
• Withdrawal causes permanent receptor loss
• Tapering only matters for topical formulations

Correct Answer: Tapering is recommended to allow HPA axis recovery after prolonged therapy

Q27. Dexamethasone is classified pharmacologically as a:

• Benzodiazepine
• Glucocorticoid corticosteroid
• Nonsteroidal anti-inflammatory drug (NSAID)
• Beta‑adrenergic agonist

Correct Answer: Glucocorticoid corticosteroid

Q28. Which adverse ocular effect may occur with prolonged systemic dexamethasone use?

• Increased intraocular pressure and cataract formation
• Permanent color blindness
• Acute bacterial conjunctivitis resistance
• Improved night vision

Correct Answer: Increased intraocular pressure and cataract formation

Q29. A practical counseling point for patients receiving oral dexamethasone is to:

• Stop abruptly when they feel better
• Take the dose in the morning to minimize insomnia
• Avoid all vaccines indefinitely
• Expect immediate relief of chronic conditions within hours

Correct Answer: Take the dose in the morning to minimize insomnia

Q30. Which monitoring is important before starting long-term dexamethasone therapy?

• Baseline blood pressure, glucose, bone density assessment, and infection screening
• No baseline monitoring is required
• Only genetic testing for CYP2D6
• Baseline audiometry only

Correct Answer: Baseline blood pressure, glucose, bone density assessment, and infection screening

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