Dosage Calculations
Doses, drips, safety
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You can always create as many flashcards as you like, free of charge.
If you would rather use a ready-made deck such as Dosage Calculations, we ask you for a small sum in return. For €1.29 once you get 100 flashcards, sorted into 14 categories and with notes that add to them. You start out learning instead of typing, and whatever you find missing later you add yourself.
- Cards
- 100
- Categories
- 14
- Price
- €1.29
Free, no account, no ads
What is in this deck
With this deck you learn dosage calculation end to end: desired over have and dimensional analysis, conversions, flow and drip rates, weight-based dosing and the safety rules around them.
Nearly every catastrophic dosing error is a decimal place. That is why an estimate before calculating is worth more than a second run through the same arithmetic.
100 cards, half of them worked. Desired over have, dimensional analysis, and the conversions that must be automatic. Then flow rates and drip rates, the drop factors, why a microdrip set makes millilitres per hour and drops per minute the same number, and how micrograms per kilogram per minute becomes something a pump will accept.
The safety cards are not padding. Why a trailing zero is forbidden and a leading one required, why U is written out, and why an implausible answer is a query about the order rather than a challenge to your own arithmetic.
The categories decide what comes up: start with “Advanced” alone and add the rest when you are ready.
What you learn
- Desired over have, and dimensional analysis
- Conversions that have to be automatic
- Flow rates, drip rates and drop factors
- Weight-based and continuous infusion dosing
- Why a trailing zero is forbidden, and other rules
The categories
14 categories sort the 100 cards. You can filter by category and take on what is due right now.
- Advanced
- Anticoagulation
- Concentrations
- Conversions
- Electrolytes
- Fluids
- Infusion
- Insulin
- Method
- Paediatrics
- Practice
- Preparation
- Safety
- Worked
What you get
Here are three of the 100 cards you get when you buy the deck.
Question
What is the basic dosage formula?
Answer
Desired over have, times the quantity.
Note
Every oral and injectable calculation reduces to it, whatever the wrapping.
Question
What is dimensional analysis in dosage work?
Answer
Setting units so the unwanted ones cancel.
Note
It is slower to write and far harder to get wrong, which is why it is taught first.
Question
How many milligrams in a gram?
Answer
1000.
Note
Moving between metric prefixes is always a factor of a thousand in drug work.
Learning with Qardbox
You see a card, you think, you turn it over and say whether you knew it. A round asks nothing more of you, and how the app works out the next date from that is on the page about FSRS-6.
What sits comes back less often, what wobbles comes back soon. You set a daily goal, and when nothing is due the app tells you exactly that instead of inventing work for you. How a round goes is shown on the learning page.
Everything stays on your device. No account, no sign-up, no ads. After the purchase the deck sits in your library like any other subject and can be studied, reordered and extended just like your own.
What it costs, and what it doesn’t
Qardbox itself costs nothing, and it stays that way. Every function is there from the start, with no subscription, no ads and no tiers; what that rests on is on the page about what it costs.
Your own cards stay unlimited, and decks from friends or from the family you read in without a limit, from a file as well. You do not need this deck in order to learn with Qardbox.
It is a shortcut: 100 checked cards for €1.29, once, with Family Sharing. The work you would otherwise do is already done. The App Store shows the price in your currency.
Common questions
Do I have to pay for Qardbox?
No. The app is free, with no subscription and no ads, and every feature is included. The only thing that costs money is a ready-made deck like this one, €1.29 once.
Could I make these cards myself?
Yes, without limit and for free. You can type them, import a file or take over cards from friends. This deck only saves you the work.
How many cards are in Dosage Calculations?
100 cards, sorted into 14 categories.
Do I need a connection to study?
Only to download the deck. After that it lives on your device and you study offline. There is no account, and you sign in nowhere.
Which devices does this run on?
On iPhone and iPad from iOS 26, and on Apple Watch. One purchase covers the family through Family Sharing.
Is there a Qardbox for Android?
No. Qardbox is there for iPhone, iPad and Apple Watch, not for Android and not in a browser.
Other decks that go with this one
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