PSI Dispensing Practice 2 — Questions and Answers
Question 1: Reconstitution of an oral antibiotic suspension requires adding which liquid?
- Freshly boiled and cooled water to the specified volume (Correct answer)
- Saline solution
- Tap water directly to the bottle mark
- Orange juice to improve taste
Correct answer: Freshly boiled and cooled water to the specified volume
Oral antibiotic suspensions (e.g., amoxicillin) are reconstituted with freshly boiled and cooled water to the volume indicated on the bottle label, then shaken well. Tap water may contain bacteria.
Question 2: A patient requires 250 mg of amoxicillin. The suspension contains 125 mg/5 mL. What volume should be dispensed per dose?
- 10 mL (Correct answer)
- 5 mL
- 2.5 mL
- 20 mL
Correct answer: 10 mL
125 mg = 5 mL, therefore 250 mg = 10 mL. Using the formula: required dose / stock strength × volume = 250/125 × 5 = 10 mL.
Question 3: Which auxiliary label should be added to tetracycline capsules?
- Avoid dairy products and antacids — take on an empty stomach (Correct answer)
- Take with food and milk
- May cause drowsiness
- Keep refrigerated after opening
Correct answer: Avoid dairy products and antacids — take on an empty stomach
Tetracyclines chelate divalent cations (Ca2+, Mg2+, Al3+) in dairy and antacids, forming insoluble complexes that reduce absorption by up to 80%. They should be taken 1 hour before or 2 hours after food/dairy.
Question 4: Methotrexate for rheumatoid arthritis is typically prescribed at which unusual frequency that requires special patient counselling?
- Once weekly (Correct answer)
- Once daily
- Twice daily
- Every 3 days
Correct answer: Once weekly
Methotrexate for inflammatory conditions is given ONCE WEEKLY — not daily. Daily use causes fatal toxicity. Fatal errors have occurred. Pharmacists must counsel patients explicitly on the once-weekly schedule.
Question 5: Which expiry date information is mandatory on dispensed prescription labels in Ireland?
- Dispensing date (the label must include the date dispensed) (Correct answer)
- Manufacturer's expiry date on every label
- Both dispensing and manufacturer expiry
- No date required on dispensed packs
Correct answer: Dispensing date (the label must include the date dispensed)
Irish dispensing regulations require the dispensing date on the dispensed label. This allows identification of how long the patient has had the medicine and aids in recall or safety follow-up.
Question 6: Which device is used to measure liquid medicines accurately for paediatric doses?
- Oral syringe (Correct answer)
- Standard kitchen teaspoon
- Measuring jug
- Dropper alone for all volumes
Correct answer: Oral syringe
Oral syringes are the most accurate method for measuring small paediatric liquid doses. Kitchen spoons are inaccurate (may hold 3–7 mL) and should never be recommended for medicine measurement.
PSI Dispensing Practice 2
Reconstitution of an oral antibiotic suspension requires adding which liquid?