Analgesic Effect of Ibuprofen 400, 600 and 800 mg, Paracetamol 500 and 1000 mg, and Paracetamol 1000 mg Plus 60 mg Codeine: Single-dose, Randomized, Placebo-controlled and Double-blind Study on Acute Pain After Third Molar Surgery

Acetaminophen (paracetamol) and related aspirin-like drugs have traditionally been used for pain control of minor to moderate postoperative pain. Gradually traditional non-steroidal anti-inflammatory drugs (NSAIDs) have become more popular as analgesics due to assumed superior therapeutic effects and aggressive marketing campaigns orchestrated by the pharmaceutical industry.

Ibuprofen is a widely used analgesic both in non-prescription and prescription doses.

A dose-response relationship for low ibuprofen doses is shown. Evidence of a progressing dose response relationship for moderate (i.e. 400 mg) to higher doses is scarce. A possible analgesic ceiling effect has been suggested for doses above 400 mg, although a correlation between given ibuprofen doses above 400 mg and patient serum levels is shown. However, it may be questioned if the plasma concentration of ibuprofen is an important determinator of analgesic drug efficacy. A higher dose is more likely to influence the duration of analgesic effect rather than the peak analgesic effect.

There are few clinical trials investigating the dose-response relationship of increasing ibuprofen doses and paracetamol doses. To our knowledge no published study has investigated the dose-response relationship of ibuprofen and paracetamol in the same trial with a negative (i.e. placebo) and a positive (i.e. best standard analgesic treatment) control group.