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Published on: July 29, 2014
Analgesic efficacy of morphine sulfate immediate release vs. oxycodone/acetaminophen for acute pain in the emergency
Catsim Fassassi1, Daniel Dove1, Ashley Davis1
1Department of Emergency Medicine, Maimonides Medical Center, Brooklyn, NY, USA.
Objective:
Previous research demonstrated that administration of Morphine Sulfate Immediate Release (MSIR) results in similar analgesic efficacy to Oxycodone but with significantly lesser degrees of euphoria and reward. The purpose of this study sit to investigate if MSIR combined with Acetaminophen can serve as an opioid analgesic alternative to Oxycodone combined with acetaminophen (Percocet) for acute pain in the Emergency Department (ED).
Methods:
A prospective, randomized, double-blind trial of ED patients aged 18 to 64 years presenting with moderate to severe acute pain as defined by an 11-point numeric rating scale (NRS) with an initial score of ≥5 (0 = no pain and 10 = very severe pain). Patients were randomized to receive either 15 mg MSIR combined with 650 mg of Acetaminophen or 10 mg Oxycodone combined with 650 mg Acetaminophen. Patients were assessed at baseline, 30, 45 and 60 min. The primary outcome was reduction in pain at 60 min. Secondary outcomes include drug likeability and adverse events.
Results:
80 patients were enrolled in the study (40 per group). Demographic characteristics were similar between the groups (P > 0.05). Mean NRS pain scores at baseline were 8.44 for the MSIR group and 8.53 for the Percocet group (P = 0.788). Mean pain scores decreased over time but remained similar between the groups: 30 min (6.03 vs. 6.43; P = 0.453), 45 min (5.31 vs. 5.48; P = 0.779), and 60 min (4.22 vs. 4.87; P = 0.346). Reduction in mean NRS pain scores were statistically significant from baseline to 30, 45 and 60 min within each group (P < 0.0001 at each time point for both groups). The largest NRS mean difference was from baseline to 60 min: 4.2 (95% CI: 3.43 to 5.01) for MSIR group and 3.61 (95% CI: 2.79 to 4.43) for Percocet group. No clinically significant changes or any serious adverse events were observed in either group.
Conclusion:
MSIR provides similar analgesic efficacy as Percocet for short-term pain relief in the ED, similar rates of nausea/vomiting, and lower rates of likeability of the drug.
Insights
Morphine Sulfate Immediate Release (MSIR) with acetaminophen offers comparable pain relief to Percocet in the ED. MSIR demonstrated similar efficacy and safety, with reduced drug likeability.
Area of Science:
- Emergency Medicine
- Pharmacology
- Pain Management
Background:
- Previous studies indicate Morphine Sulfate Immediate Release (MSIR) has comparable analgesic effects to oxycodone with less euphoria.
- Opioid analgesics are commonly used for acute pain management in the Emergency Department (ED).
Purpose of the Study:
- To evaluate if MSIR combined with acetaminophen is a viable alternative to oxycodone combined with acetaminophen (Percocet) for acute pain in the ED.
- To compare the analgesic efficacy, safety, and patient likeability of MSIR/acetaminophen versus Percocet.
Main Methods:
- A prospective, randomized, double-blind trial involving 80 adult patients with moderate to severe acute pain (NRS ≥5).
- Patients received either 15 mg MSIR/650 mg acetaminophen or 10 mg oxycodone/650 mg acetaminophen.
- Pain scores (NRS) and adverse events were assessed at baseline and at 30, 45, and 60 minutes post-administration.
Main Results:
- Both treatment groups showed statistically significant reductions in pain from baseline.
- No significant differences in pain reduction were observed between the MSIR/acetaminophen and Percocet groups at 60 minutes (mean NRS: 4.22 vs. 4.87).
- Adverse events were similar between groups, with no serious events reported. MSIR/acetaminophen had lower drug likeability ratings.
Conclusions:
- MSIR combined with acetaminophen provides similar short-term analgesic efficacy to Percocet for acute pain in the ED.
- MSIR/acetaminophen is a safe alternative to Percocet, with comparable efficacy and adverse event profiles.
- While effective, MSIR/acetaminophen was associated with lower patient likeability compared to Percocet.
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