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Investigation of Efficacy of Improved Acetaminophen Labeling

Consumer Understanding and Use of Non-Prescription Analgesics, Investigation of Efficacy of Improved Acetaminophen Labeling

Status
Completed
Phases
Unknown
Study type
Observational
Source
ClinicalTrials.gov
Registry ID
NCT01592448
Enrollment
662
Registered
2012-05-07
Start date
2012-10-31
Completion date
2013-03-31
Last updated
2014-11-18

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Acetaminophen Overdose, Pain

Keywords

Acetaminophen, Patient Safety, Health Literacy

Brief summary

The purpose of this study is to evaluate, through brief, one-on-one cognitive interviews, the efficacy of 'enhanced' acetaminophen messages and icons in improving consumer understanding and use of prescription (Rx) and non-prescription (over-the-counter, OTC) acetaminophen containing products compared to the current standard.

Detailed description

Acetaminophen is a pain reliever and fever reducer found in many over-the-counter (OTC) analgesics as well as prescription (Rx) products commonly prescribed at discharge from the emergency department. 1 An estimated 36% of Americans ingest acetaminophen at least once a month.1, 2 While acetaminophen is generally safe and effective when used at recommended doses, acetaminophen overdose has surpassed viral hepatitis as the leading cause of acute liver failure (ALF) in the United States.2-4 Moreover, one half to two-thirds of overdoses leading to acute liver failure are unintentional, suggesting the root cause may be poor understanding of medication labeling or failure to recognize the consequences of exceeding the recommended maximum daily dosage.2-4 On-going studies by this research group have shown patient misunderstanding of dosing instructions and warnings associated with OTC medicines to be prevalent. It has also been suggested that patients receiving prescription medications containing acetaminophen may not be informed or aware of the potential risk of acetaminophen overuse when taking prescription products in combination with over-the-counter pain relievers.1 This is supported by the finding that a third of narcotic users were simultaneously using an OTC acetaminophen containing product in a multicenter study of ALF cases.2 To address the growing concern of acetaminophen misuse, in June 2009 the US Food and Drug Administration (FDA) convened a panel to discuss the maximum dose recommendations of acetaminophen found in OTC medications. The panel concluded that there was a notable lack of available evidence on consumer understanding and use of over-the-counter acetaminophen products. Studies are needed to explore patients' 1) knowledge of potential acetaminophen overdose when using prescription analgesics simultaneously with non-prescription acetaminophen and 2) avenues available to increase awareness of potential acetaminophen overdose from misuse of both OTC and Rx acetaminophen containing medicines.

Interventions

BEHAVIORALActive Ingredient Icon

Enhanced bottles will have a symbol, or icon, designed to draw attention to active ingredient information. The icon is a black hexagon containing two letters denoting the active ingredient of the medication (i.e. Ac for acetaminophen). Over-the-counter bottles will have the icon placed on the front of the bottle next to active ingredient information and on the back of the bottle in the drug facts to the left of the active ingredient information. Prescription bottles will have the icon placed below the directions for how to take the medication and will be accompanied by a brief statement indicating the medicine contains acetaminophen.

Sponsors

Emory University
CollaboratorOTHER
McNeil Consumer & Specialty Pharmaceuticals, a Division of McNeil-PPC, Inc.
CollaboratorINDUSTRY
Northwestern University
Lead SponsorOTHER

Study design

Observational model
CASE_CONTROL
Time perspective
CROSS_SECTIONAL

Eligibility

Sex/Gender
ALL
Age
18 Years to 80 Years
Healthy volunteers
Yes

Inclusion criteria

* 18-80 years old * English speaking

Exclusion criteria

* Visual or hearing impairments * Moderate to severe cognitive impairments

Design outcomes

Primary

MeasureTime frameDescription
Functional Understanding and Use40 minutesFunctional understanding (via teachback and demonstration) of acetaminophen label information (OTC & Rx), including 1) active ingredient, 2) maximum daily dose, and 3) risks associated with misuse.

Secondary

MeasureTime frameDescription
Health literacy (NVS)40 minutesThe NVS (Newest Vitals Sign) is designed to provide a valid and quick assessment of participant health literacy. The assessment is based on a nutrition label from an ice cream container. Patients are given the label and then asked 6 questions about it.
Participant characteristics40 minutesBasic demographic characteristics (age, sex, race/ ethnicity), socioeconomic information (education, household income), health status information (self-reported overall health), recent medication use and beliefs about over-the-counter medicines will be collected.

Countries

United States

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026