PEBC Drug Dispensing and Compounding Flashcards

A pharmacist is preparing a compounded sterile preparation (CSP) classified as Category 2 under USP . The beyond-use date (BUD) assigned is 45 days refrigerated. Which of the following conditions MUST be met to support this BUD?

Answer: The preparation must pass sterility testing and bacterial endotoxin testing (BET) before release

Under USP , Category 2 CSPs that are assigned extended BUDs (beyond the default Category 1 limits of 12 hours at room temperature or 24 hours refrigerated) require sterility testing and bacterial endotoxin testing (BET) before patient administration. These tests are mandatory to justify the extended BUD assignment. Preparation in an ISO 5 environment is required for all sterile compounding but alone does not justify extended BUDs without testing.

A prescription is received for Methotrexate 2.5 mg tablets, with the directions 'Take 3 tablets once weekly on Sundays.' The prescriber has written '30 days supply.' How many tablets should be dispensed, and what is the most critical counselling point specific to this dispensing scenario?

Answer: Dispense 12 tablets; counsel that daily dosing is a known fatal error — dose is weekly only

30 days supply at 3 tablets once weekly = approximately 4 weeks = 12 tablets. The MOST CRITICAL counselling point specific to dispensing methotrexate is the risk of fatal overdose from daily administration — this is one of the most reported serious medication errors in practice. While folic acid, teratogenicity, and CBC monitoring are all valid counselling points, ISMP and Health Canada identify the daily-vs-weekly dosing error as the highest-priority safety message at point of dispensing.

During a final check of a ward stock narcotic kit, a pharmacist notices the tamper-evident seal on a morphine 10 mg/mL vial is intact but the vial appears to contain a slightly cloudy solution. The narcotic count reconciles correctly. What is the MOST appropriate immediate action?

Answer: Quarantine the vial, document the discrepancy, and report it as a suspected drug diversion or tampering incident

An intact seal combined with a visually abnormal product (cloudiness in a normally clear solution) is a hallmark sign of potential drug diversion via needle adulteration — a known diversion method where the drug is replaced with another substance while the seal is re-tampered. Even though the count reconciles, this finding must be treated as a suspected tampering incident. The vial should be quarantined and the incident reported to management, regulatory authorities, and law enforcement as required. Destruction alone without investigation would obscure evidence and is inappropriate.

A pharmacist is compounding a topical preparation requiring anhydrous lanolin and receives the raw material with a Certificate of Analysis (CoA) showing the peroxide value (PV) is 22 mEq/kg. What is the pharmacist's correct course of action?

Answer: Reject the raw material; lanolin with a peroxide value above 20 mEq/kg is unsuitable for compounding due to risk of sensitization

Lanolin with a peroxide value exceeding 20 mEq/kg has a significantly increased risk of causing contact sensitization and allergic reactions in patients, particularly those with compromised skin barriers. USP and compounding standards specify that anhydrous lanolin used in compounding should have a peroxide value of ≤20 mEq/kg. A CoA showing 22 mEq/kg means the raw material fails this specification and must be rejected. Shortening the BUD does not mitigate the sensitization risk inherent to oxidized lanolin.

A pharmacist receives a faxed prescription for a Schedule I controlled substance from a physician practicing in another province. The patient is currently visiting and needs an emergency supply. Under the NAPRA Model Standards and most provincial regulations, which statement BEST describes the pharmacist's authority?

Answer: The pharmacist may dispense an emergency supply at their professional discretion, but only the quantity needed for the emergency period, and must verify prescriber credentials

Under NAPRA model standards and most provincial regulations, pharmacists have professional discretion to dispense an emergency supply of a controlled substance when a patient has a legitimate therapeutic need, even from an out-of-province prescriber. However, the supply must be limited to what is necessary for the emergency period, and the pharmacist must exercise due diligence in verifying the prescriber's identity and credentials (e.g., via the prescriber's college registry). Out-of-province prescriptions for controlled substances are not automatically recognized for full supply without additional verification, distinguishing this from a standard prescription.

When performing an osmolality check for a compounded oral pediatric suspension, a pharmacist calculates the osmolality is 1,850 mOsm/kg. The prescription is for a 28-week corrected gestational age neonate. What is the MOST appropriate response?

Answer: Do not dispense as-is; reformulate or dilute the preparation, as high osmolality preparations risk necrotizing enterocolitis (NEC) in premature neonates

In premature neonates, hyperosmolar oral preparations (generally >450–600 mOsm/kg, with some guidelines citing up to 1,000 mOsm/kg as the upper limit) are associated with a significantly increased risk of necrotizing enterocolitis (NEC), a life-threatening gastrointestinal emergency. An osmolality of 1,850 mOsm/kg is grossly hyperosmolar and represents a serious patient safety risk. The preparation must be reformulated (by reducing excipient concentration or diluting with an appropriate vehicle) before dispensing. Osmolality of oral preparations is a recognized critical quality attribute in neonatal compounding.