Morphine
| Evidence Level: L4 | Predicted Indications: 10 |
Table of Contents
Morphine: From Diarrhoeal Disease to Myofascial Pain Syndrome
One-Sentence Summary
Morphine is an opioid analgesic that the knowledge graph links to diarrhoeal disease as its original indication. The TxGNN model predicts it may be effective for myofascial pain syndrome, but there are 0 clinical trials and only indirect literature (10 publications, mostly related pain conditions) supporting this direction.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Diarrhoeal disease (per the knowledge graph; the Singapore licence records contain no indication text) |
| Predicted New Indication | Myofascial pain syndrome |
| TxGNN Prediction Score | 99.75% |
| Evidence Level | L4 |
| Singapore Market Status | ✓ Marketed |
| Number of Registrations | 5 |
| Recommended Decision | Hold |
Why is This Prediction Reasonable?
Currently, detailed mechanism of action data is not available in the data compiled for this report. Based on general pharmacology, morphine is a mu-opioid receptor agonist with well-established analgesic activity. Myofascial pain has a nociceptive component, so a plausible mechanistic link exists.
However, the link is weak in practice. Opioids are not recommended as standard treatment for myofascial pain. The retrieved literature is mostly indirect: opioid use in related chronic pain conditions, a stretching-exercise cohort in "legacy pain" patients, and a randomized trial of morphine as an adjunct in surgical myofascial infiltration (not a trial in myofascial pain syndrome itself).
The original indication (diarrhoeal disease) is pharmacologically unrelated to myofascial pain, so the prediction does not rest on indication similarity.
Other predictions ranked by the model
Some other predictions have more supporting evidence than the top-ranked one:
| Rank | Predicted Indication | Score | Evidence Level | Comment |
|---|---|---|---|---|
| 4 | Restless legs syndrome | 99.47% | L3 | Opioids are recognised as an option for refractory RLS; supported by a national registry with up to 5-year follow-up and intrathecal morphine reports. Recommendation: Research Question |
| 2 | Manic bipolar affective disorder | 99.64% | L5 | Only animal-model and conceptual links; doubtful |
| 3 | Tourette syndrome | 99.48% | L5 | Reviews and preclinical work only |
| 6 | Migraine disorder | 99.32% | L4 | Guidelines generally discourage opioids; potential for harm |
| 5, 7–10 | ADHD (inattentive), trichotillomania, methemoglobinaemia, migraine with brainstem aura, specific developmental disorder | 99.06–99.34% | L5 | No meaningful supporting evidence |
Clinical Trial Evidence
Currently no related clinical trials registered for myofascial pain syndrome.
(For reference, the only registered trial among the ten predictions relates to restless legs syndrome: NCT01476124, a Phase 1, completed, 18-participant crossover study of the pharmacokinetics and tolerability of morphine with gabapentin enacarbil in healthy volunteers. It does not assess efficacy.)
Literature Evidence
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 41664327 | 2026 | RCT | Asian Spine J | Dexmedetomidine plus morphine vs plain ropivacaine for myofascial infiltration in spinal fusion surgery (adjunct use, not myofascial pain syndrome) |
| 35066974 | 2022 | Cohort | Pain Pract | Structured stretching programme for myofascial pain and opioid use in "legacy pain" patients |
| 39793344 | 2025 | Clinical study | Eur J Obstet Gynecol Reprod Biol | Pudendal nerve block for perioperative pain after botulinum toxin injection for myofascial pelvic pain; not morphine-specific |
| 21419546 | 2011 | Review | J Oral Maxillofac Surg | Long-term opioid use in temporomandibular joint dysfunction can be neither supported nor refuted by current evidence |
| 16967674 | 2006 | Review | J Calif Dent Assoc | Medications, infusions and injections for differential diagnosis of orofacial pain |
Singapore Market Information
| Authorization Number | Product Name | Dosage Form | Approved Indication |
|---|---|---|---|
| SIN05508P | MST CONTINUS TABLET 30 mg | Tablet, film coated | Not stated in the data |
| SIN05506P | MST CONTINUS TABLET 10 mg | Tablet, film coated | Not stated in the data |
| SIN00757P | DBL MORPHINE SULFATE INJECTION 10 mg/ml | Injection | Not stated in the data |
| SIN16891P | MORPHINE SULFATE KALCEKS SOLUTION FOR INJECTION 10MG/ML | Injection, solution | Not stated in the data |
| SIN13598P | Morphine-hameln 10 mg/ml Injection | Injection, solution | Not stated in the data |
Both oral (modified-release tablet) and injectable forms are available locally. All 5 registrations are valid single-ingredient products.
Safety Considerations
Contraindication signals from the knowledge graph (not label text) include: hypertension, orthostatic hypotension, long QT syndrome/torsades de pointes, liver failure and liver disease, kidney disease, COPD, epilepsy, pancreatitis, gallbladder disease, hypothyroidism, psychotic and other mental disorders, anxiety disorders, gastric ulcer, and potassium deficiency.
Drug Interactions (100 interactions found; examples):
- Major: fentanyl, codeine, dihydrocodeine, tramadol, butalbital, dichloralphenazone, alprazolam, ethanol (additive central nervous system and respiratory depression is the main concern)
- Moderate: chlorpheniramine, cetirizine, nifedipine, hydrochlorothiazide, metformin, alfentanil, among others
For warnings and label contraindications, please refer to the package insert.
Conclusion and Next Steps
Decision: Hold
Rationale: The top-ranked prediction (myofascial pain syndrome) has no registered trials and only indirect literature, and opioids are not a recommended standard treatment for it. Among the ten predictions, restless legs syndrome has the strongest support (L3, with registry and case-series data) and is the most reasonable candidate to take forward as a research question.
To proceed, the following is needed:
- The HSA package insert warnings and contraindications (a blocking gap for safety screening)
- Mechanism of action data (for example from DrugBank)
- For restless legs syndrome: a controlled morphine-specific efficacy study, plus a risk assessment covering dependence, dose escalation and sleep-disordered breathing
- For myofascial pain syndrome: direct comparative evidence against standard care, with a clear opioid-risk justification
- A safety plan addressing the major interactions with other opioids, benzodiazepines and alcohol
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.