4 Dose and Quantity Calculations Free Online FlashCards

How do you calculate a dose written in mg/kg/dose?

Multiply the dose per kilogram by the patient’s weight in kilograms to find the amount for one administration: $\frac{\mathrm{mg}}{\mathrm{kg}\cdot\mathrm{dose}}\times\mathrm{kg}=\frac{\mathrm{mg}}{\mathrm{dose}}$.

How do you calculate a dose written in mg/kg/day when it is divided into doses?

Multiply by the patient’s weight to find the total daily amount, then divide by the number of daily administrations to find the amount per dose.

What is each dose for $4$ mg/kg/day in $2$ doses for a patient weighing $15$ kg?

The daily amount is $4\times15=60$ mg/day. Dividing into $2$ equal doses gives $30$ mg per dose.

How do you convert a weight in pounds to kilograms?

Convert pounds to kilograms by dividing by $2.20462$: $\mathrm{kg}=\frac{\mathrm{lb}}{2.20462}$.

What is the difference between mg and mL?

$\mathrm{mg}$ measures the amount of drug; $\mathrm{mL}$ measures liquid volume. They describe different quantities.

What is the concentration in mg/mL for $30$ mg per $5$ mL?

Divide the drug amount by the liquid volume: $\frac{30\ \mathrm{mg}}{5\ \mathrm{mL}}=6\ \mathrm{mg/mL}$.

How do you calculate the liquid volume for a prescribed dose?

Divide the prescribed dose in mg by the concentration in mg/mL: $\mathrm{volume\ (mL)}=\frac{\mathrm{dose\ (mg)}}{\mathrm{concentration\ (mg/mL)}}$.

What volume supplies a $90$ mg dose from a liquid containing $30$ mg per $5$ mL?

The concentration is $6$ mg/mL, so $90\div6=15$ mL per dose.

How many doses per day does an every-12-hours schedule specify?

A schedule every $12$ hours corresponds to $2$ doses per day.

How do you calculate the total quantity for a fixed schedule?

Multiply the quantity per dose by doses per day and by the number of days: $\mathrm{total\ quantity}=\mathrm{quantity\ per\ dose}\times\mathrm{doses/day}\times\mathrm{days}$.

What total liquid volume covers $1.5$ mL per dose, twice daily, for $5$ days?

The volume is $1.5$ mL per dose and the schedule is $2$ doses per day for $5$ days, so the total is $1.5\times2\times5=15$ mL.

How do you calculate days’ supply when daily use is known?

Divide the total quantity dispensed by the quantity used per day: $\mathrm{days\ supply}=\frac{\mathrm{total\ quantity}}{\mathrm{quantity\ used\ per\ day}}$.