August 7, 2013
Flow Resistors: Second Line of Defense With Children’s
Liquid Medications

Atlanta—A new study found that flow restrictors successfully slow down young children’s access to liquid medications, and the authors are calling for more widespread use of the devices to prevent accidental ingestion.

The study, published online by the Journal of Pediatrics, notes that more than 500,000 calls are made to poison control centers each year after accidental ingestion of medications by young children, even as child-resistant packaging for most medications has contributed to the prevention of thousands of pediatric deaths in the United States.

For the study, researchers from the CDC, Emory University, and the Georgia Poison Center sought to determine whether adding flow restrictors to bottles can limit the amount of liquid medication a child could access, even if child-resistant caps are missing or improperly closed.

“Caregivers must correctly resecure the cap after each and every use. If the cap is not correctly resecured, children can open and drink whatever medication is in the bottle,” according to co-author Daniel S. Budnitz, MD, MPH.

Determining that a second line of defense could give parents and caregivers more time to intervene before the child drinks the liquid, the researchers looked at whether adapters added to the neck of a bottle had any effect on the ability of children to access the medication and how long it took them to do that.

For the study, 110 children, aged 3 to 4 years, participated in two tests with harmless liquids. In one test, the children were given an uncapped medication bottle with a flow restrictor, and in the other test, the children received either a traditional bottle without a cap or with an incompletely closed child-resistant cap. In both cases, they were instructed to remove as much liquid as possible in 10 minutes.

After the first 2 minutes, the children were able to empty 96% of bottles without caps and 82% of bottles with incompletely closed caps. None of the uncapped bottles with flow restrictors were emptied before 6 minutes, however, and just 6% of children succeeded in emptying bottles with flow restrictors during the 10-minute test period. Overall, 11% of children were able to remove more than 25 mL of liquid from uncapped bottles with flow resistors, according to the study.

Study authors note that older children generally were more successful than younger children at removing liquid from the flow-resistant bottles, and that none of the youngest children—ranging in age from 36 to 41 months—were able to remove as much as 5 mL of test liquid, the amount in a standard dose of acetaminophen for a 2- to 3-year-old child. In 2011, drug manufacturers voluntarily added flow restrictors to OTC infant acetaminophen.

“Our findings suggest that adding [flow restrictors] to liquid medicine bottles limits the accessibility of their contents to young children and could complement the safety provided by current child-resistant packaging,” according to the report. The authors suggest it is especially important to add the adapters to liquid medications that can be harmful in small doses, although they add that flow restrictors are not the complete solution.

"Flow restrictors are designed as a secondary barrier and caregivers should not rely on flow restrictors alone; adding flow restrictors could complement the safety provided by current child-resistant packaging," cautioned study co-author Maribeth C. Lovegrove, MPH. She urged pharmacists and other health professionals to routinely educate caregivers on the importance of consistently locking child-resistant caps and storing medications away and out of sight of children.

U.S. Pharmacist Social Connect