SNLE Pharmacology 3 — Questions and Answers
Question 1: What is the purpose of using a Z-track technique for IM injections?
- To prevent medication from leaking back into subcutaneous tissue and minimize skin staining (Correct answer)
- To speed up absorption
- To reduce pain only
- To inject into deeper muscle tissue
Correct answer: To prevent medication from leaking back into subcutaneous tissue and minimize skin staining
The Z-track technique (pulling the skin 2–3 cm laterally before injecting, releasing after withdrawing) creates a zigzag track that seals the medication in the muscle, preventing backtracking into subcutaneous tissue. It is required for medications that stain skin (iron dextran) or are irritating.
Question 2: A patient taking corticosteroids long-term should be monitored for which complication?
- Hyperglycemia, hypertension, osteoporosis, and adrenal suppression (Correct answer)
- Hypoglycemia only
- Bradycardia
- Hypotension
Correct answer: Hyperglycemia, hypertension, osteoporosis, and adrenal suppression
Long-term corticosteroid use causes multiple side effects: hyperglycemia (impaired glucose metabolism), hypertension (sodium/water retention), osteoporosis (reduced calcium absorption), weight gain (Cushing's syndrome), immunosuppression, and hypothalamic-pituitary-adrenal axis suppression.
Question 3: What is 'bioavailability' of a drug?
- The fraction of an administered dose that reaches systemic circulation unchanged (Correct answer)
- The speed of drug absorption
- The volume of distribution
- The half-life of a drug
Correct answer: The fraction of an administered dose that reaches systemic circulation unchanged
Bioavailability is the proportion of drug that reaches systemic circulation in an active form. IV administration has 100% bioavailability. Oral bioavailability is reduced by first-pass metabolism, poor absorption, and chemical instability. It affects dosing route and amount.
Question 4: Which drug is used to reverse opioid overdose?
- Naloxone (Narcan) (Correct answer)
- Flumazenil
- N-acetylcysteine
- Atropine
Correct answer: Naloxone (Narcan)
Naloxone is a competitive opioid receptor antagonist that rapidly reverses opioid-induced respiratory depression, sedation, and miosis. It has a short duration (30–90 minutes) — shorter than most opioids — so repeated doses or infusion may be needed.
Question 5: A patient is prescribed furosemide (a loop diuretic). What electrolyte should be monitored?
- Potassium (risk of hypokalemia) (Correct answer)
- Calcium (risk of hypercalcemia)
- Phosphate (risk of hyperphosphatemia)
- Magnesium (risk of hypermagnesemia)
Correct answer: Potassium (risk of hypokalemia)
Loop diuretics inhibit Na-K-2Cl transport in the loop of Henle, causing loss of sodium, potassium, chloride, magnesium, and calcium. Hypokalemia is the most clinically significant electrolyte disturbance, increasing the risk of cardiac arrhythmias.
Question 6: What is the mechanism of action of proton pump inhibitors (PPIs)?
- Irreversibly inhibit the H+/K+-ATPase pump in gastric parietal cells, reducing acid secretion (Correct answer)
- Neutralize stomach acid
- Block histamine H2 receptors
- Coat the stomach lining
Correct answer: Irreversibly inhibit the H+/K+-ATPase pump in gastric parietal cells, reducing acid secretion
PPIs (omeprazole, pantoprazole, esomeprazole) irreversibly block the proton pump (H+/K+-ATPase) in gastric parietal cells, producing the most potent and long-lasting reduction in gastric acid secretion. They are first-line for peptic ulcer disease and GERD.
SNLE Pharmacology 3
What is the purpose of using a Z-track technique for IM injections?