There is a way to study pharmacology that does not work: making a list of every drug in every class and trying to hold it. There is a way that does: learning, for each common condition, the first-line class, the one or two things that disqualify it, and what you monitor afterwards.
That framing matches how items are written. The stem gives a straightforward condition, then adds one detail — a pregnancy, a creatinine, an allergy, a comorbidity — and the correct answer is the alternative that detail forces you to.
This is exam-preparation material, not prescribing guidance
Drug recommendations, dosing and safety warnings change. Nothing here should be used to treat a patient. Confirm every clinical decision against current guidelines, the product labelling and your own formulary.
The five questions to ask of every pharmacology item
- What is the condition, plainly stated? Strip the vignette to a diagnosis.
- What is the first-line class for that condition in an uncomplicated patient?
- What in this stem disqualifies it? Allergy, pregnancy, age, renal or hepatic function, comorbidity, interacting drug.
- What is the alternative once it is disqualified?
- What would I monitor after starting it? Many items stop at this step and never ask about choice at all.
Step three is where the points are. If a stem mentions a laboratory value, a pregnancy test or another medication, it is not background — it is the pivot.
Modifiers that change the answer
| Detail in the stem | What it usually signals |
|---|---|
| Pregnancy or "planning pregnancy" | Rules out several common classes outright — ACE inhibitors and ARBs among the most heavily tested |
| Reduced renal function | Dose adjustment or avoidance; metformin and many antimicrobials are frequent subjects |
| Age over 65 | Think fall risk, anticholinergic burden, sedation, and potentially inappropriate medications |
| "Penicillin allergy" | The item wants an alternative — and often wants you to distinguish intolerance from true anaphylaxis |
| Asthma or reactive airway disease | Caution with non-selective beta blockade |
| A second medication listed for no obvious reason | An interaction question in disguise |
| Heart failure, gout, hyperkalaemia, hepatic disease | Comorbidity-driven exclusions within an otherwise reasonable class |
Contraindications worth knowing without hesitation
- ACE inhibitors and ARBs in pregnancy — fetal toxicity. Also avoid the combination of the two, and watch potassium and renal function after starting either.
- Live vaccines in pregnancy and in significant immunosuppression.
- Aspirin in children with febrile viral illness — Reye syndrome.
- Nitrates with phosphodiesterase-5 inhibitors — profound hypotension.
- Combining serotonergic agents without regard for serotonin syndrome, and MAOIs with almost anything.
- Beta blockade in decompensated heart failure, and caution with non-selective agents in reactive airway disease.
- Metformin in significant renal impairment and around iodinated contrast.
- Fluoroquinolones where a safer alternative exists, given tendon, neurological and aortic warnings.
Monitoring: the other half of the blueprint
A large share of pharmacology items ask what you check and when, not what you start. Learn monitoring alongside the drug, never separately.
| Class | Typically monitored |
|---|---|
| ACE inhibitors / ARBs | Potassium and renal function after initiation and dose changes; cough as a class effect of ACE inhibitors |
| Diuretics | Electrolytes, renal function, volume status |
| Statins | Baseline liver enzymes; investigate significant muscle symptoms |
| Metformin | Renal function; B12 with long-term use |
| Thyroid replacement | TSH after an interval sufficient to reach steady state, not days later |
| Warfarin | INR, plus a long list of dietary and drug interactions |
| Lithium, digoxin, phenytoin | Serum levels — narrow therapeutic index drugs are heavily tested |
| SSRIs in young people | Suicidality warning; close early follow-up |
How to build the knowledge efficiently
Learn classes, not brands
Recognise the stems: -pril for ACE inhibitors, -sartan for ARBs, -olol for beta blockers, -statin, -prazole, -cillin, -floxacin. Once you know what the class does and what it is contraindicated in, individual members are largely interchangeable for exam purposes.
Build one card per condition, not per drug
Front: "Uncomplicated condition X, otherwise healthy adult — first-line class?" Back: the class, one contraindication, one monitoring parameter. That single card format covers all three of the ways the topic gets asked.
Study the alternatives deliberately
For every first-line agent, know what you use when it is not available. Penicillin allergy, pregnancy, renal impairment and paediatric age are the four substitutions that generate the most items.
Populations that carry their own rules
- Pregnancy and lactation. Expect at least one item where the pregnancy is the entire question. Know which common classes are avoided and where the safer alternatives sit.
- Paediatrics. Weight-based dosing, formulations, and the small set of drugs avoided in children.
- Older adults. Reduced clearance, polypharmacy, anticholinergic load, sedation and fall risk. Familiarity with the concept of potentially inappropriate medications is expected.
- Renal and hepatic impairment. The stem gives you a number for a reason.
Two habits that raise the score
Read the last line before the vignette. "Which is the most appropriate initial treatment" and "which laboratory value should be monitored" are different questions with different correct answers drawn from the same scenario. Knowing which one is being asked before you read the details keeps you from answering the item you expected.
Treat every stray clinical detail as load-bearing. Board vignettes are written tightly. A creatinine, a last menstrual period, an existing prescription and an allergy field are not decoration — each one is there because it eliminates an option.
Key points
- The question is usually about the modifier — the allergy, the pregnancy, the renal function, the comorbidity.
- Learn drug classes and their contraindications, not brand-by-brand trivia.
- Know the small set of absolute contraindications cold; they turn a hard item into an easy one.
- Monitoring parameters and black box warnings are tested as often as initial choice.