Study objectives: To evaluate the efficacy and prevalence of side effects of hydrocodone versus codeine in acute pain syndromes. TYPE OF PARTICIPANTS/SETTING: Sixty-two consecutive adult emergency department patients 18 to 70 years old with acute musculoskeletal pain. Patients using other analgesics or having any contraindication to opioid therapy were excluded. In addition, 12 patients were excluded because of insufficient data or study dropout.
Design/interventions: In a randomized, double-blind prospective manner, patients received either 5 mg hydrocodone with 500 mg acetaminophen or 30 mg codeine with 500 mg acetaminophen to take on discharge from the ED and every four hours thereafter as needed for pain.
Measurements: Pain intensity was evaluated by a visual analog scale at zero, one, two, four, eight, 24, and 48 hours. Specific side effects were sought, along with the number of patients reporting inadequate analgesia.
Main results: Data were obtained on 50 subjects (25 per group). Mean and median pain scores did not differ significantly at time zero (x vs y, 6.03 vs 5.99 and 6.8 vs 6.1, respectively) or subsequent intervals. Side effects were noted in eight hydrocodone/acetaminophen and 18 codeine/acetaminophen patients (P = .005). No significant differences in gastrointestinal side effects were reported; however, less nausea or vomiting was reported in the hydrocodone group (P = .23). Central nervous system side effects (sedation or lightheadedness) were reported in six hydrocodone/acetaminophen patients compared with 16 codeine/acetaminophen patients (P less than .005). In addition, no hydrocodone/acetaminophen patients reported inadequate analgesia compared with six codeine/acetaminophen patients (P less than .05).
Conclusion: Although pain scores were not significantly different, hydrocodone may be a more effective analgesic than codeine in acute musculoskeletal pain, as demonstrated by significantly fewer treatment failures. Central nervous system side effects are less common with hydrocodone than with codeine.