Drug calculation trainer
Dose, rate and clearance calculations, with the working shown
Ten kinds of calculation that every prescriber and nurse gets tested on, with fresh numbers every time and a step-by-step solution the moment you answer. No two exercises repeat.
- Weight-based and surface-area doses, infusion rates, concentrations, dilutions and unit conversion
- Pharmacokinetic calculations: loading dose, maintenance dose and Cockcroft-Gault creatinine clearance
- Answers checked with a tolerance, and the working shown whether you were right or wrong
Included in
- Free20 a day
- Student ProUnlimited
- Faculty ProUnlimited
- InstitutionUnlimited
Every new account also starts with a 7-day Student Pro trial, no card.
How a session works
1
Pick a type, or let it pick
Ten exercise types. Practise one you find hard, or take them at random the way an exam would.
2
Work it out
A single-line question with realistic values. Enter a number in the unit asked for.
3
Check
Right or wrong against a tolerance, and the correct answer either way.
4
See the working
The formula, the substitution and the result, step by step, so the method sticks rather than the number.
Try it now, no account
Try a few now
Three exercises generated for you, then as many more as you like. The numbers are random, the marking is the trainer's own, and every answer comes with the working.
What gets marked
Weight-based dosing
mg per kg for adults, and mg per kg per day divided into doses for children.
Surface-area dosing
mg per square metre from a given body surface area.
Infusions and dilutions
Pump rates from volume and time, drug content of percentage solutions, and volumes to draw up from a stock concentration.
Loading and maintenance doses
From volume of distribution, target concentration, bioavailability and clearance.
Creatinine clearance
Cockcroft-Gault with the sex correction, the number every renal dose adjustment starts from.
Unit conversion
Grams, milligrams and micrograms, where most real-world dosing errors begin.
Courses that use this module
Each of these courses builds this practice into its modules, next to the teaching it tests.
- Therapeutic Drug Monitoring and Prescribing Calculations
For final-year medical students preparing for finals and the Prescribing Safety Assessment (PSA), final-year pharmacy students, and foundation doctors. Topics: prescribing calculations, applied pharmacokinetics and therapeutic drug monitoring of narrow-therapeutic-index drugs, and interpreting potassium, sodium, renal, thyroid and liver results. UK practice, BNF dosing and NICE-style guidance. Pharmacy students do not sit the PSA.
Questions
- Is this free?
- The free tier includes a daily allowance of exercises, and Student Pro and above are unlimited. The sample on this page needs no account at all.
- Are the numbers realistic?
- Yes. Weights, doses per kilogram, concentrations and clearances are drawn from ranges you would meet on a ward, and the drug names are ones you will prescribe.
- Does it track my progress?
- Signed in, every attempt is recorded with its type, so you can see your accuracy by calculation type and go back to the ones you get wrong.
- How strict is the marking?
- Each exercise carries a tolerance, typically one to three percent, so a rounding difference is not marked wrong. The worked solution shows the exact figure.
Start practising today
Create a free account and your first session is a minute away. No card.