Introduction
Understanding appetite stimulants and suppressants is essential for B.Pharm students learning pharmacological actions, mechanisms, clinical uses and adverse effects. This topic covers central and peripheral regulators of appetite—hypothalamic neuropeptides (NPY/AgRP, POMC), neurotransmitters (serotonin, norepinephrine, dopamine, histamine, endocannabinoid) and gut hormones (ghrelin, leptin). You will study representative drugs: megestrol, dronabinol, cyproheptadine, mirtazapine, amphetamine-like anorectics, orlistat and GLP-1 agonists—focusing on receptor targets, pharmacokinetics, safety, contraindications and drug interactions. These MCQs focus on mechanism-based reasoning, clinical decision-making and common exam patterns relevant to pharmacy practice. Now let’s test your knowledge with 30 MCQs on this topic.
Q1. Which hypothalamic neuronal populations are primarily responsible for increasing and decreasing appetite?
- Paraventricular nucleus neurons only
- Arcuate nucleus: NPY/AgRP (orexigenic) and POMC/CART (anorexigenic)
- Lateral hypothalamus only
- Ventromedial nucleus: dopamine/serotonin neurons
Correct Answer: Arcuate nucleus: NPY/AgRP (orexigenic) and POMC/CART (anorexigenic)
Q2. What is the primary mechanism by which amphetamine-like anorectics suppress appetite?
- Inhibition of pancreatic lipase
- Agonism at CB1 receptors
- Increased synaptic norepinephrine and dopamine release in hypothalamic centers
- Peripheral blockade of ghrelin receptors
Correct Answer: Increased synaptic norepinephrine and dopamine release in hypothalamic centers
Q3. Which drug reduces dietary fat absorption by inhibiting pancreatic lipase?
- Orlistat
- Phentermine
- Dronabinol
- Megestrol acetate
Correct Answer: Orlistat
Q4. Dronabinol stimulates appetite primarily by acting on which receptor?
- CB1 cannabinoid receptor
- 5-HT2C serotonin receptor
- H1 histamine receptor
- Alpha-2 adrenergic receptor
Correct Answer: CB1 cannabinoid receptor
Q5. Megestrol acetate increases appetite through which pharmacological class/action?
- Progestin with appetite-stimulating and anti-inflammatory effects
- Selective serotonin reuptake inhibition
- Peripheral lipase activation
- CB1 receptor antagonism
Correct Answer: Progestin with appetite-stimulating and anti-inflammatory effects
Q6. Cyproheptadine increases appetite mainly via antagonism of which receptors?
- Muscarinic M3 receptors
- H1 histamine and 5-HT2 serotonin receptors
- Dopamine D2 receptors
- Beta-adrenergic receptors
Correct Answer: H1 histamine and 5-HT2 serotonin receptors
Q7. Mirtazapine promotes weight gain and appetite primarily by blockade of which receptor?
- 5-HT1A agonism
- Alpha-2 adrenergic agonism
- H1 histamine receptor antagonism and 5-HT2/3 antagonism
- CB2 receptor antagonism
Correct Answer: H1 histamine receptor antagonism and 5-HT2/3 antagonism
Q8. Which cardiovascular adverse effect is most associated with amphetamine-like appetite suppressants?
- Bradycardia and hypotension
- Hypertension and tachycardia
- Aortic stenosis
- Pulmonary embolism without blood pressure change
Correct Answer: Hypertension and tachycardia
Q9. A common gastrointestinal side effect of orlistat is:
- Constipation
- Steatorrhea and oily stools
- Upper GI bleeding
- Severe pancreatitis in all patients
Correct Answer: Steatorrhea and oily stools
Q10. Megestrol acetate is mainly indicated for which clinical scenario?
- Acute migraine prophylaxis
- Anorexia-cachexia syndrome in cancer or HIV patients
- Long-term weight loss in obesity
- First-line therapy for type 2 diabetes
Correct Answer: Anorexia-cachexia syndrome in cancer or HIV patients
Q11. Which condition is an absolute contraindication for many centrally acting anorectic agents?
- Controlled hypothyroidism
- Uncontrolled hypertension or cardiovascular disease
- Well-managed asthma
- Stable depression on SSRI therapy
Correct Answer: Uncontrolled hypertension or cardiovascular disease
Q12. Fenfluramine was associated with valvular heart disease due to agonism at which receptor?
- Beta-1 adrenergic receptor
- 5-HT2B serotonin receptor
- GABA-A receptor
- CB1 receptor
Correct Answer: 5-HT2B serotonin receptor
Q13. Lorcaserin (withdrawn) produced appetite suppression by selective agonism of which receptor subtype?
- 5-HT1B
- 5-HT2A
- 5-HT2C
- 5-HT3
Correct Answer: 5-HT2C
Q14. Which class of drugs commonly increases appetite and weight as a side effect due to glucocorticoid effects?
- SGLT2 inhibitors
- Glucocorticoids (e.g., prednisone)
- Beta-blockers
- ACE inhibitors
Correct Answer: Glucocorticoids (e.g., prednisone)
Q15. Which anti-obesity drug used in diabetes reduces appetite via GLP-1 receptor agonism?
- Liraglutide
- Orlistat
- Megestrol acetate
- Cyproheptadine
Correct Answer: Liraglutide
Q16. Blockade of central H1 histamine receptors typically results in:
- Appetite suppression and insomnia
- Appetite stimulation and sedation
- Severe diarrhea
- Enhanced lipase activity
Correct Answer: Appetite stimulation and sedation
Q17. Rimonabant, a CB1 antagonist developed as an anti-obesity agent, was withdrawn mainly because of:
- Severe hepatotoxicity in all subjects
- Poor oral absorption
- Psychiatric adverse effects including depression and suicidality
- Irreversible renal failure
Correct Answer: Psychiatric adverse effects including depression and suicidality
Q18. Topiramate contributes to weight loss by which central mechanisms?
- Enhancing GABAergic activity and inhibiting AMPA/kainate glutamate receptors
- Stimulating CB1 receptors
- Inhibiting lipase in the GI tract
- Selective serotonin reuptake
Correct Answer: Enhancing GABAergic activity and inhibiting AMPA/kainate glutamate receptors
Q19. A notable adverse effect associated with megestrol acetate includes:
- Increased risk of thromboembolism and fluid retention
- Severe hypoglycemia
- Acute pancreatitis in most patients
- Permanent alopecia
Correct Answer: Increased risk of thromboembolism and fluid retention
Q20. Which statement about orlistat pharmacokinetics is correct?
- It is highly bioavailable with systemic effects
- It has minimal systemic absorption and acts locally in the gut
- It is administered intravenously for rapid effect
- It accumulates in adipose tissue extensively
Correct Answer: It has minimal systemic absorption and acts locally in the gut
Q21. Sibutramine, a withdrawn anti-obesity agent, exerted weight loss by which mechanism?
- Peripheral CB1 agonism
- Inhibition of pancreatic lipase
- Inhibition of serotonin and norepinephrine reuptake (SNRI)
- Direct activation of leptin receptors
Correct Answer: Inhibition of serotonin and norepinephrine reuptake (SNRI)
Q22. Combining MAOI antidepressants with certain serotonergic anorectics can cause which dangerous interaction?
- Hyponatremia only
- Serotonin syndrome or hypertensive crisis
- Prolonged QT shortening
- Increased pancreatic lipase activity
Correct Answer: Serotonin syndrome or hypertensive crisis
Q23. Which of the following drugs is a synthetic THC indicated as an appetite stimulant?
- Nabilone
- Phentermine
- Dronabinol
- Orlistat
Correct Answer: Dronabinol
Q24. Which receptor antagonism by mirtazapine is most directly linked to its appetite-increasing effect?
- 5-HT1A antagonism
- H1 histamine antagonism
- Muscarinic M2 antagonism
- Dopamine D1 antagonism
Correct Answer: H1 histamine antagonism
Q25. Leptin decreases appetite primarily by acting on which neuronal pathway?
- Stimulating NPY/AgRP neurons to increase feeding
- Activating POMC neurons and inhibiting NPY/AgRP neurons
- Directly binding to ghrelin receptors in the stomach
- Blocking GLP-1 receptors centrally
Correct Answer: Activating POMC neurons and inhibiting NPY/AgRP neurons
Q26. Which drug is NOT used as an appetite stimulant?
- Cyproheptadine
- Megestrol acetate
- Orlistat
- Dronabinol
Correct Answer: Orlistat
Q27. Which commonly prescribed short-term appetite suppressant requires monitoring for increased heart rate and blood pressure?
- Phentermine
- Mirtazapine
- Megestrol acetate
- Orlistat
Correct Answer: Phentermine
Q28. A frequent CNS adverse effect of cannabinoid-based appetite stimulants like dronabinol is:
- Severe neutropenia
- Euphoria, dizziness and somnolence
- Profound bradycardia
- Significant hypoglycemia
Correct Answer: Euphoria, dizziness and somnolence
Q29. Which stimulant is FDA-approved for moderate to severe binge-eating disorder and reduces appetite?
- Lisdexamfetamine
- Rimonabant
- Orlistat
- Megestrol acetate
Correct Answer: Lisdexamfetamine
Q30. Which gut hormone produced in the stomach strongly stimulates appetite and is often elevated before meals?
- Leptin
- Insulin
- Ghrelin
- Peptide YY
Correct Answer: Ghrelin
