Why speed decides the PSA
Candidates who fail rarely fail on knowledge; they fail because each answer took four minutes of scrolling. Use the web BNF at bnf.nice.org.uk, because that is what the exam links to; the app and the book arrange content differently, so speed built there does not fully transfer.
Which heading is this? A which-drug-caused-the-rash question is a side-effects lookup. A dose-in-kidney-disease question is a renal-impairment lookup. Naming the heading first turns a monograph into a ten-second visit.
BNF quick map
The question asks about one thing. Go to the heading that owns it.
The search workflow
- Decide what you needDose, interaction, side effect, monitoring, advice, or a treatment choice. One word.
- Search the generic name, or the conditionGeneric names resolve to the monograph almost every time; combination products live under their combination name (co-amoxiclav, co-codamol). For a treatment choice, search the condition, not a drug.
- Jump to the headingUse the page's contents, or press Ctrl+F (Cmd+F) and type the word you care about: renal, hypokalaemia, monitoring.
- Confirm the patient-specific modifierRenal function, age band, pregnancy, the other drug on the chart. It is usually a sub-heading of the same section.
- Return to the questionAnswer, or flag and move on if the lookup is not converging inside a minute.
The shape of a monograph
Every drug page follows the same order: indications and dose, then contra-indications, cautions, interactions, side effects, then the special groups (renal impairment, hepatic impairment, pregnancy, breast feeding), then monitoring requirements and patient advice. Knowing that order cold is the single biggest speed gain, because you stop reading pages and start jumping to the one heading the question is really about.
Where each exam section lives
Checking interactions between medicines
Open either drug's monograph and follow its Interactions link. That opens an A to Z list of everything the drug interacts with; scan alphabetically for the other medicine and note the severity label.
A chart with six drugs has fifteen possible pairs and you cannot check them all. The vignette almost always points at the suspect: the drug started this week, the new symptom, the rising creatinine. Check the one or two pairs the story implicates.
A new macrolide against a statin. Trimethoprim against methotrexate. An NSAID beside an ACE inhibitor and a diuretic on the same chart. Anything newly started against warfarin.
Side effects: the frequency bands are the answer
Side effects are grouped by how often they occur, from very common to rare. When a question asks which medicine caused a symptom, you are not looking for whether a drug can cause it; almost anything can. You are looking for the drug that lists it as common or very common while the others do not, with a start date that fits. Frequency plus timing acquits the decoys.
Renal impairment: go straight to the heading
When a question hands you an eGFR or creatinine clearance, it is telling you where the answer lives. The renal impairment section states dose reductions or avoidance against kidney-function bands; match the patient's number to the band. Watch the distinction the exam tests repeatedly: drugs that are dangerous to kidneys, and drugs that accumulate because of failing kidneys. Both live under the same heading.
Contra-indications outrank cautions. When the exam wants a stop-this-drug or avoid-this-option answer, it is nearly always built on a contra-indication. Check that list first; it is shorter and more decisive.
Seven drills, thirty seconds each
Open the BNF in another tab, press start, and find it. The first run takes minutes; by the third run most take seconds, and that difference is the marks the PSA awards for speed. The answer under each drill says where it is, not what it says: the point is the route.
Find the maximum daily dose of a common oral analgesic for an adult.
Where it is
Search the generic name, open Indications and dose, read the maximum under the adult indication. Two headings, one number.
From any statin's page, find whether it interacts with clarithromycin and how severely.
Where it is
Monograph, then the Interactions link, then scan alphabetically to C. Note the severity label.
Find the eGFR at which a direct oral anticoagulant needs a dose change or should be avoided.
Where it is
Monograph, Renal impairment. The bands are stated against creatinine clearance or eGFR.
Find whether a beta blocker is contraindicated in asthma, and where it says so.
Where it is
Monograph, Contra-indications. It is a class contra-indication, so the class page says it too.
From a treatment summary, name the first-line antibiotic for an adult with low-severity community-acquired pneumonia.
Where it is
Search the condition, not a drug. The treatment summary lists first line by severity.
Find which electrolyte a loop diuretic commonly disturbs, using the side-effects section only.
Where it is
Monograph, Side-effects, read the common band.
Find the monitoring requirements for methotrexate.
Where it is
Monograph, Monitoring requirements. Note baseline, scheduled and what to tell the patient to report.
Which BNF section should I use?
Five scenarios. Pick the heading you would open first.
1. A patient develops muscle pain two weeks after starting a statin. Where do you look first?
Side-effects. Side-effects, and the frequency band myalgia sits in. Then Interactions, because a newly added drug can raise the statin's level, and Monitoring requirements for what to check.
2. The eGFR is 28 mL/min and the patient is due a new anticoagulant. Where do you look?
Renal impairment. Renal impairment states the dose reduction or avoidance threshold by kidney function band. The dose section gives the usual dose, which is the wrong one here.
3. You need first-line treatment for newly diagnosed hypertension in a 48-year-old. Where do you look?
Treatment summaries. Search the condition. The treatment summary sets out first-line choices by age and family origin, in step order. Only then open the chosen drug's monograph.
4. A woman starting an antiepileptic asks what she must know. Where do you look?
Patient and carer advice, and Important safety information. Patient and carer advice carries the counselling points; the important safety information box carries any regulator warning, which for some antiepileptics is the whole answer.
5. Two drugs on a chart, a rising INR. Where do you look?
Interactions. Open either monograph's Interactions and find the other drug in the alphabetical list. The severity label tells you how seriously to take it.
On the day
- Pace by marks: a 10-mark prescribing item has earned six minutes, a 2-mark item barely one.
- If a lookup is not converging inside a minute, flag the question and move on.
- Do the lookup even when you are sure; confirmation costs ten seconds.
- Write the dose in a unit, never a volume, and write micrograms in full.
- Read every prescription once more before you finish, as a nurse would.
This guide is free to link to, print and use in teaching sessions. It prints as a clean handout, and every section has a stable anchor, for example /bnf-guide/#map for the quick map and /bnf-guide/#drills for the drills.
The other half of the skill is answering exam-style questions with the BNF open and the clock running
733 questions and 11 full papers timed at the real pace, with the BNF technique above baked into every explanation. Twenty questions are free.