APC Intern Written Exam common mistakes
APC Intern Written Exam · Understand the traps and how to avoid them.
Calculating a dose or dilution and writing the first answer without re-checking the units, so a result in milligrams is reported where grams or micrograms were required, or a percentage concentration is treated as a ratio strength.
Under time pressure the arithmetic step feels finished once a number appears, and the unit conversion is treated as clerical rather than as part of the calculation; candidates also conflate w/v percentage with mg/mL without writing the conversion down.
What to do instead
Adopt a fixed three-line layout for every calculation: given values with units, conversion factors written explicitly, then the answer with unit and a sanity check (is this dose plausible for an adult, is the volume plausible for the container). Re-read the question's requested unit before moving on.
Applying adult standard doses to paediatric, renal, or hepatic patients without adjusting for weight, body surface area, or organ function.
Memorised adult doses are the most fluently recalled facts, so they surface first; candidates underestimate how often the exam expects a mg/kg calculation, a maximum-dose cap, or a reduced dosing interval.
What to do instead
Before answering any dosing question, state the patient's weight, age, and renal/hepatic status from the vignette, then ask which adjustment applies. Practise a standard workflow: calculate mg/kg, compare against the adult maximum, then check whether renal function requires interval extension.
Answering interaction and contraindication questions from a single drug pair in isolation, ignoring the patient's comorbidities and concurrent medicines listed in the scenario.
Candidates pattern-match the named drug pair they recognise and stop reading, missing that the actual hazard in the question comes from a third medicine, a disease state, or a duplicated therapeutic class.
What to do instead
Read the whole vignette and list every medicine and condition before evaluating the pair. Train on the habit of asking 'what else is this patient on, and what else do they have?' and check for therapeutic duplication and cumulative risk, not just the highlighted interaction.
Choosing a counselling or dispensing answer that is technically correct but omits the mandatory legal or professional step, such as verifying the prescription's legal validity, checking for the prescriber's registration, or documenting the intervention.
Clinical content dominates candidates' revision, so the legal wrapper around a supply is treated as background; candidates answer the pharmacology question they see rather than the practice question being asked.
What to do instead
For every practice scenario, run a checklist: is the prescription legally valid and complete, is the supply authorised for this schedule, has the patient been identified, and has the action been recorded. Build this checklist into practice so it becomes automatic.
Mixing up look-alike/sound-alike medicine names and abbreviations, selecting the wrong strength or formulation of a drug with a similar name.
Recognition memory for familiar drug names is strong, and exam questions deliberately place confusable names close together; fatigue late in the paper increases reliance on partial word recognition.
What to do instead
When a drug name appears, slow down and read the full name, strength, and formulation aloud mentally. Maintain a personal list of confusable pairs encountered in study and review it before the exam rather than relying on recognition alone.
Losing marks on multi-step questions by answering only the first part, for example giving the dose but not the volume to administer, or the recommendation but not the rationale.
Candidates read the opening clause, recognise a familiar task, and start writing; the second requirement is embedded later in the sentence or in a following line and is missed under time pressure.
What to do instead
Underline or mentally number every instruction word in the stem ('calculate', 'state', 'justify') before answering, then tick each one off in the response. In practice, mark your own answers against the number of required elements.
Confusing pharmacokinetic parameters, such as half-life with time to steady state, clearance with volume of distribution, or bioavailability with bioequivalence.
These terms cluster conceptually and are learned as definitions rather than as relationships, so under exam pressure the definitions blur and the candidate picks the option that sounds most familiar.
What to do instead
Learn each parameter through its equation and its clinical consequence (for example, roughly four to five half-lives to steady state, and what that means for loading doses). Practise explaining each term in one sentence with a worked example.
Handling extemporaneous compounding and concentration questions without checking whether the requested strength is achievable or whether a stock formulation should be used instead.
Candidates focus on getting the arithmetic right and skip the professional judgement step about whether the product should be compounded at all, or whether the resulting concentration exceeds solubility or stability limits.
What to do instead
After any compounding calculation, add a judgement line: is this strength commercially available, is it pharmaceutically feasible, and what beyond-use date and labelling apply? Treat feasibility as part of the answer, not an optional extra.
Defaulting to a 'refer to the prescriber' or 'refuse the supply' answer whenever a scenario contains any ambiguity, rather than identifying the proportionate professional action.
Uncertainty makes the most cautious option feel safest, and candidates without practice experience over-weight escalation; exams often reward the intermediate step such as clarifying with the patient, checking the record, or supplying with counselling.
What to do instead
Learn the graded options in professional decision-making: gather information, clarify, counsel, document, then escalate if unresolved. Practise ranking options by proportionality so escalation is chosen when the risk justifies it, not as a reflex.
Running out of time because early questions are over-answered and later calculation questions are rushed or left blank.
Candidates allocate effort by interest rather than by marks, and calculation questions feel slower so they are deferred until the end, when there is no time to check them.
What to do instead
Do a first pass answering confident questions quickly, flag calculations and long vignettes, and return to them with reserved time. In practice, time yourself on mixed sets so you learn your personal pace and build in a checking window.