Abstract
BACKGROUND: Acetaminophen (APAP) is an immensely popular analgesic agent that is sold in Canada without prescription. The incidence of APAP toxicity leading to acute liver failure has increased over the past two decades. Recent data from a US cohort study demonstrates that up to 46% of acute liver failure cases are due to APAP. Published data suggest that accidental hepatotoxicity related to therapeutic misuse of APAP is a relatively common occurrence, especially when APAP is combined with alcohol. It is unclear if patients are aware of differences in dosage formats of APAP and increased potential for hepatotoxicity when APAP is combined with alcohol. AIMS: The aim of this study was to assess patient understanding of APAP, dosage formats, combination with alcohol, and potential for toxicity. METHODS: A survey was given to consecutive patients aged ≥ 18 attending a general gastroenterology clinic in Vancouver, BC. Data collection for this study began in September 2018 and is ongoing. Fisher’s exact test was used to compare categorical variables. P-values were calculated as 2-tailed and a value of ≤ 0.05 was interpreted as significant. RESULTS: This preliminary analysis included 95 respondents, some did not answer all questions. The majority of respondents were female (n=52/94, 54.7%). A majority identified as having university-level education (n=63/94, 67.0%) and Caucasian ethnicity (n=69/94, 73.4%). A minority reported using “regular-strength (RS)” APAP (325mg PO) more than one day per week (n=23/94, 24.5%). A similar number of respondents reported used “extra-strength (ES)” APAP (650mg PO) more than one day per week (n=21/93, 22.6%). Respondents more commonly reported using both RS and ES APAP together over a given stretch of time (n=14/92, 15.2%), than RS APAP alone (n=8/92, 8.7%) or ES APAP alone (n=6/92, 6.5%) (p<0.01). Most recognized that APAP toxicity is harmful to the liver (n=76/91, 83.5%). A majority (n=50/86, 58.1%) misunderstood the distinction between RS and ES APAP – believing that the ES formula included the addition of a separate analgesic agent (n=36/86, 41.9%) or was a different drug altogether than RS APAP (n=14/86, 16.3 %). A minority identified that APAP in combination with alcohol leads to increased toxicity (n=42/89, 47.2%). CONCLUSIONS: Patients seen in an outpatient GI clinic have a general understanding that APAP may lead to liver toxicity. Concerningly, however, those who frequently use APAP products seem to use both regular and extra-strength formulations together. Additionally, there is a low-level of understanding regarding the differences in these formulations. Data collection is ongoing, and we will seek to stratify those patients at risk for misunderstanding APAP dosage formats. FUNDING AGENCIES: None