Early bioavailability of paracetamol after oral or intravenous administration
Abstract
BACKGROUND: Paracetamol is a peripherally acting analgesic commonly used in multimodal post-operative pain management to reduce the need for more potent analgesics with their unwanted side-effects. The dose and optimal galenical form for achieving analgesic concentrations is not well defined. The primary aim of this pilot project was to study the early bioavailability for two fixed doses of orally administrated paracetamol and one dose of intravenous propacetamol, all of which were given after minor surgery.
METHODS: Thirty-five patients undergoing day surgery were divided into five groups, seven patients each. Groups received either 1 g of an ordinary paracetamol tablet, 2 g of an ordinary paracetamol tablet, 1 g of a bicarbonate paracetamol tablet, 2 g of a bicarbonate paracetamol tablet or 2 g intravenously of prodrug propacetamol. We studied the plasma concentration of paracetamol during the first 80 min after administration.
RESULTS: Within 40 min, intravenous propacetamol gave a median plasma paracetamol concentration of 85 micromol/l (range 65-161) and decreased thereafter. After oral administration, median plasma paracetamol concentration increased with increasing dose and time, but there were huge inter-individual differences at all time points studied. At 80 min after oral paracetamol the median plasma concentrations were 36 and 129 micromol/l for the 1- and 2-g groups, respectively, with an overall range between 0 and 306 micromol/l.
CONCLUSION: Oral…
How strong is the evidence?
Evidence Hub reads this as a randomized trial, done in people. Its evidence level is 2 of 5 (High · randomized trial). Randomized trials of a reasonable size are the strongest single-study design.
Read the paper
Related studies
- Effect of dexamethasone as an analgesic adjuvant to multimodal pain treatment after total knee arthroplasty: randomised clinical trial
- Effect of a Postoperative Multimodal Opioid-Sparing Protocol vs Standard Opioid Prescribing on Postoperative Opioid Consumption After Knee or Shoulder Arthroscopy: A Randomized Clinical Trial
- Comparison of the Post-Caesarean Analgesic Effect of Adding Dexmedetomidine to Paracetamol and Ketorolac: A Randomized Clinical Trial
- A triple-blind randomized clinical trial of different associations between dexamethasone and non-steroids anti-inflammatories for preemptive action in third molar extractions
- An open label randomized clinical trial of Indomethacin for mild and moderate hospitalised Covid-19 patients
- Oral paracetamol and/or ibuprofen for treating pain after soft tissue injuries: Single centre double-blind, randomised controlled clinical trial
Go deeper in Evidence Hub
Evidence Hub adds a study data sheet (design, sample size, evidence level, key numbers), an AI summary and a chat grounded in the paper's text.