A clinical trial comparing ibuprofen, 400, 600, and 800 mg, with aluminum ibuprofen, 400 mg, and placebo was conducted in patients with moderate or severe pain subsequent to third molar extraction. Pain intensity ratings and ibuprofen serum levels were obtained at baseline, 30 minutes, 1 hour, and hourly thereafter for 3 hours. Pain intensity ratings were also obtained at hours 4, 5, and 6. Serum levels at 1, 2, and 3 hours correlated significantly with the log dose of ibuprofen (r = 0.35, 0.49, and 0.48, respectively) and with global analgesic response as measured by the percentage of the sum of the pain intensity scores (r = 0.28, 0.34, and 0.26, respectively). However, possibly because of differences in drug formulation, the percentage of the sum of the pain intensity scores did not correlate significantly with log dose. The highest correlations were found between contemporaneous serum levels and pain intensity difference values, particularly at hour 1 (r = 0.54). Our results support the proposition that increased ibuprofen serum levels lead to increased analgesia.

The efficacy and safety of graded doses (10, 20, and 30 mg) of controlled-release (CR) oxycodone was compared with that of immediate-release (IR) oxycodone (15 mg), immediate-release oxycodone 10 mg in combination with acetaminophen 650 mg (APAP), and placebo in a single-dose, double-blind, randomized, parallel-group study. The participants, 182 inpatients experiencing moderate to severe pain after abdominal or gynecologic surgery, provided hourly ratings of pain intensity and relief for 12 hours after administration. All active treatments were significantly superior to placebo for many hourly measurements and for the sum of pain intensity differences (SPID) and total pain relief (TOTPAR). A dose response was found among the three levels of CR oxycodone for pain relief and peak pain intensity difference (PID), with the 20- and 30-mg doses being significantly better than the 10-mg dose. For all active treatments, peak PID and peak pain relief occurred approximately 2 to 4 hours after administration. The median time to onset of relief was 32 minutes for oxycodone plus APAP, 41 minutes for IR oxycodone, and 46 minutes for CR oxycodone 30 mg. Duration of pain relief showed that the 10-, 20-, and 30-mg doses of CR oxycodone had durations of action of 10 to 12 hours compared with IR oxycodone and oxycodone plus APAP (both approximately 7 hours). Typical adverse events, particularly somnolence, occurred in all active treatment groups. Treatment with CR oxycodone was safe and effective in this study, and its characteristics will be beneficial in the treatment of pain.