Wow this is nuts:
In the new trial, Chang and colleagues enrolled 411 patients who arrived in one of two Bronx, New York, emergency rooms with acute pain in a limb. The enrolled patients were all between 18 and 64 years old, cleared of complicating health conditions, had no history of allergies or signs of opioid addiction, and were on no medications that might interact with the pain treatments. When they arrived, the patients had a mean pain score of 8.7 on a standard 11-point scale.
Researchers then randomly assigned the patients to get one of four pain-pill combinations: 400mg of ibuprofen and 1,000mg of acetaminophen; 5mg of oxycodone and 325mg of acetaminophen; 5mg of hydrocodone and 300mg of acetaminophen; or 30mg of codeine and 300mg of acetaminophen. Each of the pill combinations looked identical to the patients—three opaque capsules.
Two hours later, the patients scored their pain again. There were no statistically significant differences in pain reduction across the four groups. Mean scores dropped by 4.3 with ibuprofen and acetaminophen; 4.4 with oxycodone and acetaminophen; 3.5 with hydrocodone and acetaminophen; and 3.9 with codeine and acetaminophen. The biggest difference between any two of the groups was 0.9—oxycodone and acetaminophen vs hydrocodone and acetaminophen—which is not a clinically significant difference in pain level.