Related Experiment Video
Updated: May 8, 2026
07:09
The Sciatic Nerve Cuffing Model of Neuropathic Pain in Mice
Published on: July 16, 2014
Opioids for neuropathic pain
Ewan D McNicol1, Ayelet Midbari, Elon Eisenberg
1Departments of Anesthesiology and Pharmacy, Tufts Medical Center, Box #420, 800 Washington Street, Boston, Massachusetts, USA, 02111.
The Cochrane Database of Systematic Reviews
|August 30, 2013
Summary
Opioids show some short-term efficacy for neuropathic pain, but evidence is equivocal. Intermediate-term studies suggest benefit, yet are prone to bias. Further research is needed for long-term effects and safety.
Area of Science:
- Pharmacology and Pain Management
- Evidence-Based Medicine
- Clinical Trial Analysis
Background:
- The use of opioid agonists for neuropathic pain is controversial due to limited and equivocal study results.
- Previous reviews highlighted small study sizes and lack of long-term benefit-risk data for neuropathic pain.
- This updated review reassesses opioid efficacy and safety in neuropathic pain management.
Purpose of the Study:
- To systematically evaluate the efficacy and safety of opioid agonists in treating neuropathic pain.
- To synthesize evidence from randomized controlled trials (RCTs) on opioid treatment for neuropathic pain.
Main Methods:
- Searched multiple databases (CENTRAL, MEDLINE, EMBASE) up to October 2012 for relevant RCTs.
- Included RCTs of opioid agonists for central or peripheral neuropathic pain, excluding combination therapies or specific administration routes.
- Independent data extraction by two authors focusing on demographics, diagnoses, interventions, efficacy, and adverse events.
Main Results:
- Thirty-one trials involving 10 different opioids were included.
- Short-term (acute) exposure showed contradictory pain relief results; intermediate-term (≤12 weeks) studies demonstrated opioid efficacy over placebo (NNTB=4.0 for ≥33% pain relief).
- Common adverse events included constipation (34%), drowsiness (29%), and nausea (27%), leading to higher withdrawal rates than placebo (13% vs. 4%).
Conclusions:
- Short-term opioid efficacy for neuropathic pain intensity remains equivocal.
- Intermediate-term efficacy is suggested but potentially biased by study limitations (small size, short duration, dropout handling).
- Further RCTs are crucial to determine long-term efficacy, safety (including addiction), and quality of life impacts.
Related Concept Videos
01:15Opioid Analgesics: Synthetic and Semisynthetic Opioids
Synthetic and semisynthetic opioids are pivotal in pain management and tackling opioid addiction. Semisynthetic opioids, including morphinans (morphine derivatives), oxycodone, oxymorphone, hydrocodone, and hydromorphone, have improved pharmacokinetic profiles compared to morphine. Additionally, heroin and 6-MAM (6-Monoacetylmorphine) show better CNS penetration than morphine due to heightened lipid solubility. Hydromorphone, a potent opioid, undergoes hepatic metabolism to form the active...
01:25Analgesia and Pain Management
Pain is critical to various clinical pathologies, provoking an urgent need for effective management. Pain, whether acute or chronic, is a complex neurochemical process. Its alleviation depends on the type, with nonopioid analgesics effective for mild to moderate pain, such as musculoskeletal or inflammatory pain, while neuropathic pain responds best to anticonvulsants, tricyclic antidepressants, or serotonin/norepinephrine reuptake inhibitors. For severe acute or chronic pain, opioids may be...
01:20Opioid Analgesics: Morphine and Other Natural Cogeners
Opioids are a class of drugs that mimic endogenous opioid peptides and act on opioid receptors, and help in pain relief. These compounds are classified as natural, synthetic, or semi-synthetic. Natural opioids, like morphine, codeine, and thebaine, are derived from the opium poppy plant (Papaver somniferum or Papaver album) and are termed opiates. Synthetic opioids are artificial, while semi-synthetic opioids combine natural and synthetic compounds. Morphine, a prototypical opioid, possesses a...
01:22Opioid Receptors: Overview
Opioid receptors, including the mu (μ, MOR), delta (δ, DOR), and kappa (κ, KOR) types, belong to the rhodopsin family of G protein-coupled receptors. These receptors are located throughout the central and peripheral nervous systems and in non-neuronal tissues such as macrophages and astrocytes. Opioid receptor ligands can be categorized into agonists or antagonists. Highly selective agonists include [d-Ala2, MePhe4, Gly(ol)5]-enkephalin or DAMGO for MOR, [D-Pen2, D-Pen5]-enkephalin or DPDPE for...
01:17Drugs Affecting GI Tract Motility: Opioids as Antidiarrheal Agents
Diarrhea, a condition marked by frequent loose or watery bowel movements, can be triggered by multiple factors such as viral or bacterial infections, food intolerances, anxiety, medications, and digestive disorders. Symptoms may include abdominal pain, bloating, nausea, and cramping. Severe or prolonged diarrhea can lead to complications like electrolyte imbalances, malnutrition, and dehydration if left untreated.
Opioids, widely used antidiarrheal agents, mitigate diarrhea by slowing down...
Opioids, widely used antidiarrheal agents, mitigate diarrhea by slowing down...
01:20Pain
Pain serves as a critical warning signal that alerts the body to potential or actual harm. When mechanical pressure on the skin is intense, such as from a sharp pinch, the sensation transitions from touch to pain. Similarly, extreme temperatures, like a hot pot handle, convert the sensation of heat into pain. Pain can also result from overstimulation of other senses, such as blinding light, loud noise, or the intense heat from habañero peppers. This ability to sense pain is essential for...