Which statement correctly describes macrodrip and microdrip infusion systems?

• A. Macrodrip delivers larger drops (60 gtt/mL); microdrip delivers small drops (10 gtt/mL)
• B. Macrodrip delivers larger drops (10–20 gtt/mL); microdrip delivers small drops (60 gtt/mL)
• C. Macrodrip delivers small drops (60 gtt/mL) for precise infusions; microdrip delivers large drops (10–20 gtt/mL)
• D. Macrodrip delivers small drops; microdrip large

Answer: (B)

Drip factors dictate how many drops make up one milliliter, which changes how you pace an IV infusion. Macrodrip uses bigger drops, typically 10, 15, or 20 gtt per mL, while microdrip uses smaller drops, commonly 60 gtt per mL. Because each drop is larger with macrodrip, you need fewer drops per minute to reach the same milliliters per hour, making it faster for delivering larger volumes but offering less precise control. Microdrip, with many small drops, allows finer control and is especially useful when doses are small or precision matters, such as in pediatric infusions or delicate medications. So the description that macrodrip delivers larger drops in the 10–20 gtt/mL range and microdrip delivers 60 gtt/mL is correct. The other options would swap or reverse the drop sizes, which doesn’t reflect how these systems function.