The Institute for Safe Medication Practices (ISMP) recently pointed out that measuring doses with certain oral syringes can be confusing for healthcare practitioners and patients, and that this can lead to overdoses.

This type of syringe is packaged with drugs such as morphine sulfate concentrated oral solution. The plunger inside the syringe has a pointed end instead of a flat one. It is made that way so there is less residual solution in the syringe after the drug is delivered. But some people do not understand what part of the plunger to line up against the markings on the syringe barrel when they’re measuring the dose.

The correct way to measure the dose is to align the widest part of the syringe plunger with the calibrated markings on the barrel. If the tip of the plunger is mistakenly used to line up the dose, the plunger will be pulled too far out and the syringe will contain more than the intended dose.

ISMP cites a case where the nursing staff in several long term care facilities may have done just that — measured doses incorrectly by using the tip of the plunger to line up the dose. ISMP notes that the Medication Guide for Roxane’s morphine sulfate oral solution gives detailed instructions to patients on how to use the syringe properly, but nurses, pharmacists and other healthcare professionals should also be reminded about the right way to measure a dose with these syringes.