Drug Calculations questions made simple for nursing students.

Drug Calculations questions made simple for nursing students. This course involves mathematical calculations. First of all one must know some basic skills in change of subjects, multiplications, substraction, addition and substraction operations. How to work the questions becomes easier if these basic skills have been established.

A typical example is given below:

Question one try:
A patient has been prescribed 80mg of drug x orally. The stock dose available is 10mg , how many tablets does he needs?

Questions of this nature is straight forward and does not need much effort.
One must first of all know the conversion of the various units, thus from liters to milliliters, from grams to kilograms and so on.The unit of measure must be same at point in time.
Looking at the question above the answer is Simple and straight forward. Simple arithmetic will give you 8. But we need a more comprehensive approach that is acceptable. One must adopt the right method or fomular. This simple formular can be used:
What is been prescribed/ dose available × what is in

=80mg/10mg × 1
=8mg as your answer.

Question two try question;

A patient has been prescribed 500mg of drug x in liquid form. The stock dose available is 1.25h/10ml, how much dose does he need?

Solution; Using the formular given above;

What is been prescribed/ dose available × what is in
=500mg/1.25g×10m
Milligram and kilogram can not match and so all the units must be the same. You can easily change 500mg to g by dividing 500 by 1000. This will give you =0.5g

0.5g/1.25g × 10m
In this case we will have;
0.5g /1.25g×10
=4m

The grams will cancel each other.

One can also decided to change the units from grams to mg

In this case it will be given as;

500gm/1.25×1000×10m

= 500gm/12,500mg × 10m

0.4 × 10m

=4m