AI-powered clinical summaries delivered to your inbox 3 times per week. Evidence-based insights in 300 words, designed for busy physicians.
Subscribers receive email summaries and access to our interactive AI-powered article rankings.
Opioids improved pain only during short treatment.
*Systematic review/meta-analysis of randomized trials; Level 1a.
Froentjes LS, Barrington CAM, Craig RA, et al. Impact of treatment duration on the effectiveness of opioid analgesia. Br J Gen Pract. 2026. doi:10.3399/BJGP.2025.0705
Opioids are often prescribed for chronic pain, but prolonged use may increase pain sensitivity or tolerance. This review tested whether benefit fades with treatment duration.
Adults with chronic low back pain or osteoarthritis. Exclusions included cancer, postsurgical pain, sciatica, inflammatory arthritis, opioid use disorder, non-self-administered opioids, tramadol, tapentadol, and enriched-withdrawal trials.
Self-administered opioid medicines.
Placebo or opioid-minimized pain management.
Primary: at least 30% pain improvement. Secondary: pain score (0–100; 10 points is clinically important).
Short: ≤4 weeks; intermediate: 4–12 weeks; long: ≥12 weeks.
| Outcome | Duration | Finding | Meaning |
|---|---|---|---|
| Meaningful pain relief (primary) | ≤4 weeks | 42% more likely with opioids; number needed to treat ≈7 | Clinically meaningful; moderate certainty |
| Meaningful pain relief (primary) | 4–12 weeks | NS | Unclear benefit; low certainty |
| Meaningful pain relief (primary) | ≥12 weeks | NS | No meaningful benefit; trend favored control |
| Pain score (secondary) | ≤4 weeks | 6.1 points lower with opioids | Statistical, not clinically important |
| Pain score (secondary) | 4–12 weeks | 4.3 points lower with opioids | Statistical, not clinically important |
| Pain score (secondary) | ≥12 weeks | NS | No clear benefit |
NS = no statistically significant difference.
Trials generally used modified intention-to-treat; missing responder data counted as nonresponse. Most controls were placebo, not full active usual care.
Probable publication bias favored opioids. Trials varied widely in drug, dose, duration, and control. Several had unclear or high risk of bias. Short and intermediate pain-score differences were below the clinically important threshold.
Unfunded; University of Alberta in-kind support; no company funding.
Avoid initiating opioids for chronic low back pain or osteoarthritis when long-term treatment is likely; reserve, if ever, for brief monitored use.
Create your account in seconds using your Google account. No passwords to remember.
Get AI-curated clinical summaries delivered to your inbox three times per week (Monday, Wednesday, Friday).
Our interactive article rankings allow you to find the best articles, tailored to you.