PSA Cheat Sheet 2026

The 30 highest-yield PSA facts, distilled from real exam questions. Print it, save it as a PDF, or study it here — free, no sign-up.

1. What is the difference between rate control and rhythm control in atrial fibrillation? → Rate control slows the heart rate; rhythm control attempts to restore normal sinus rhythm
2. Which drug combination creates the greatest additive risk of QT prolongation and torsades de pointes? → Amiodarone and sotalol
3. Which condition would most likely increase cyclosporine blood levels and require downward dose adjustment? → Co-administration of fluconazole
4. A patient has a serum potassium of 2.8 mEq/L with ECG changes showing U waves. What is the most appropriate management? → IV potassium replacement with cardiac monitoring
5. Which pharmacokinetic change in elderly patients most significantly increases ADR risk from renally cleared drugs? → Progressive decline in glomerular filtration rate
6. Which topical agent is licensed for localized peripheral neuropathic pain such as postherpetic neuralgia? → Lidocaine 5% medicated plaster
7. What does 'stat' mean in a prescription or medication order? → Immediately — the medication should be given right away
8. A patient reports a documented penicillin allergy with a previous anaphylactic reaction. Which antibiotic should be prescribed with the most caution? → Cefalexin (first-generation cephalosporin)
9. A patient with HFrEF previously on ramipril is being switched to sacubitril/valsartan. What is the minimum washout period required after stopping ramipril? → 36 hours
10. What fluids should be prescribed for high calcium levels? → NaCl over 4 hours with no potassium
11. A 25-year-old develops anaphylaxis after a bee sting with urticaria, hypotension, and bronchospasm. What is the first-line treatment? → Epinephrine 0.3mg IM (1:1,000 solution)
12. A patient develops a persistent dry cough 3 weeks after starting ramipril for hypertension. What is the most appropriate management? → Switch to an angiotensin receptor blocker
13. A patient on theophylline for COPD has a level of 22 mcg/mL (therapeutic 10–20 mcg/mL). Which symptom is most consistent with theophylline toxicity? → Seizures
14. A morbidly obese patient (BMI 48, actual body weight 145 kg) requires vancomycin dosing. Which weight should be used to calculate the initial dose? → Adjusted body weight
15. What prescribing risks exist during pregnancy? → Drugs may cross the placenta and cause teratogenic effects on the developing fetus
16. A woman at 34 weeks gestation develops severe pre-eclampsia with a BP of 175/112 mmHg. What is the first-line drug treatment? → IV labetalol
17. A 77-year-old man with HFrEF is considered for spironolactone 25mg daily. His eGFR is 26 mL/min. What is the primary prescribing concern? → Severe hyperkalaemia risk due to reduced renal potassium excretion
18. Which pharmacokinetic/pharmacodynamic parameter best predicts the efficacy of vancomycin against MRSA? → AUC/MIC ratio
19. A breastfeeding mother needs analgesia following a Caesarean section. Which analgesic should be used with the greatest caution? → Codeine
20. Which of the following drugs is LEAST likely to cause QTc interval prolongation? → Metformin
21. A patient with a known peptic ulcer requires analgesia for mild-to-moderate pain. Which is the safest choice? → Paracetamol 1 g QDS
22. A Type B adverse drug reaction is best characterized by which of the following features? → Idiosyncratic and unrelated to normal drug pharmacology
23. Which drug combination constitutes the renal 'triple whammy' associated with acute kidney injury? → NSAIDs + ACE inhibitors (or ARBs) + loop or thiazide diuretics
24. A patient has eGFR of 20 mL/min/1.73m². Which pharmacokinetic parameter is most directly altered for a drug that is 90% renally excreted? → Total drug clearance
25. A patient with CKD stage 4 (eGFR 22) requires opioid analgesia. Which opioid is relatively preferable with appropriate dose reduction? → Oxycodone
26. A prescription for metformin 1000 mg b.i.d. instructs the patient to take the drug how many times per day? → Twice
27. How many refills are permitted for a Schedule II controlled substance prescription in the US? → No refills are permitted
28. Which pair represents a classic and clinically dangerous look-alike/sound-alike (LASA) medication risk? → Metformin and methotrexate
29. A patient on digoxin presents with bradycardia, nausea, and reports seeing yellow-green halos around lights. What is the most likely explanation? → Digoxin toxicity
30. Creatinine clearance (CrCl) is primarily used to guide dose adjustment for which category of drugs? → Drugs that are predominantly renally excreted unchanged