True or False poll no. 54
Canadian Agency for Drugs and Technologies in Health (CADTH)
A higher dose of acetaminophen (1000 mg) for post-surgery is associated with a higher risk of adverse events than a lower dose (650 mg).
FALSE
An evidence review of the clinical efficacy and safety of acetaminophen doses (1000 mg and 600 or 650 mg) for pain relief has shown that a single dose of 1000 mg is more effective in relieving pain than a single dose of 650 mg, and that the risk of adverse events is similar between the two doses.
Acetaminophen is a widely used, well-tolerated over-the-counter drug for pain or fever relief. Despite its safety profile, acetaminophen overdosing is responsible for about 4000 admissions to hospital per year in Canada, many of them owing to unintentional overdose. To improve safety, Health Canada is considering a decrease in the maximum recommended daily dose of acetaminophen.
A review by CADTH evaluated relevant evidence in two systematic reviews and one randomized controlled trial. Although more patients who were taking acetaminophen 1000 mg for general postoperative pain reported at least one adverse event (headache, nausea or dizziness) compared with patients taking a 600 or 650 mg dose, the risk of adverse events was similar between the two doses. No serious adverse events were reported for the treatment of postsurgical dental pain in patients taking the 1000 mg dose.
More patients taking acetaminophen 1000 mg reported pain relief of at least 50% over six hours compared with patients taking acetaminophen 600 or 650 mg.
This evidence examined only single-dose acetaminophen (not recommended maximum daily dose) and is limited to postsurgical pain conditions.
For more details, read the full report at www.cadth.ca/1000mg-versus-650-mg-acetaminophen-pain-or-fever-review-clinical-efficacy