Write down the total volume of IV liquid, in milliliters (ml).
Write down the required length of time for administering the prescribed IV solution, and convert to minutes. For instance, a prescription might require 1,200 ml over the course of 10 hours. In this case, multiply 10 by 60 to get 600.
Divide the volume by time. Example: 1,200 divided by 600 equals 2. Write that number at the top of your page.
Read the prescription and find the drop factor.
Multiply the drop factor by the previous product. In our example, if the drop factor is 20, then you would multiply 20 by 2, and the answer is 40. The drops per minute in this equation is 40.