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Strong opioid analgesic Pregnancy: Not recommended for use in pregnancy - there are no adequate data in pregnant women and animal studies have shown reproductive toxicity; regular use during pregnancy may cause drug dependence in the foetus, leading to withdrawal symptoms in the neonate. Administration during labour may depress respiration in the neonate and an antidote for the child should be readily available. Newborns whose mothers received opioid analgesics during pregnancy should be monitored for neonatal withdrawal (abstinence) syndrome. Administration to nursing women is not recommended as morphine may be secreted in breast milk and may cause respiratory depression in the infant.

Morphine Sulphate (Burns Analgesia)

Brand names: Zomorph, MST Continus, Oramorph

Morphine sulphate is a strong opioid agonist used as a mainstay of acute and procedural analgesia for burn injuries, given parenterally for severe pain and during dressing changes and debridement.

Auto-extracted from the source labelling — not yet independently clinician-verified. These values were distilled from the UK SPC (or the US label where noted) but have not had a clinician sign-off. Confirm against the current SmPC before prescribing.

Adult dose

Dose: Adults and children over 12 years, intravenous Patient Controlled Analgesia (PCA): loading doses of typically between 1 mg and 10 mg (maximum 15 mg) of morphine sulfate may be given by intravenous infusion over four or five minutes, the loading dose depending on the patient's diagnosis and condition; then an initial PCA demand dose of 1 mg with a lockout period of 5 to 10 minutes.
Route: Intravenous injection via a PCA system - the 1 mg/ml solution should NOT be diluted before use; inspect visually and use only clear solutions practically free from particles. PCA must only be carried out in departments and by staff trained and experienced in the system, and patient selection must ensure the patient is capable of understanding and following the instructions of the medical/nursing staff. Specific department or unit protocols must be followed to ensure aseptic transfer of the vial contents to the PCA system.
Frequency: Loading dose over 4 to 5 minutes, then patient-triggered 1 mg demand doses with a 5 to 10 minute lockout
Max: Loading dose maximum 15 mg; demand-dose amounts may vary depending on the loading dose, the tolerance and condition of the patient, and whether a background infusion of morphine is being given
Source: eMC SPC for Morphine Sulfate 1 mg/ml solution for injection (https://www.medicines.org.uk/emc/product/5008/smpc), section 4.2. There is considerable variation in analgesic requirements between patients, so individualised treatment strategies are required and dosage should be based on the severity of the pain and the response and opiate tolerance of the patient. Monitor the patient specifically for pain, sedation and respiratory rate during the first few hours of treatment to confirm the dosage regimen is suitable. Before initiating, agree a treatment strategy with the patient including treatment duration, treatment goals and a plan for ending treatment, in accordance with pain management guidelines; maintain frequent physician-patient contact during treatment. Keep the duration of treatment to a minimum and do not use for longer than necessary; taper the dose gradually before discontinuation, as an abstinence syndrome may be precipitated if opioid administration is stopped suddenly. In the absence of adequate pain control, consider hyperalgesia, tolerance and progression of underlying disease. ELDERLY: morphine doses need to be reduced in elderly patients. CHILDREN: 'Not recommended for children under 12 years' - no paediatric per-kg regimen is given in this SPC. SCOPE LIMIT: this SPC is for a PCA-specific intravenous presentation. It contains NO oral, intramuscular, subcutaneous or continuous intravenous infusion regimen, and no procedural / dressing-change bolus regimen - the oral, infusion and procedural figures this burns page also carries must be sourced separately from the appropriate product SPCs. The US label in this bundle (MORPHINE SULFATE, Ascend Laboratories, LLC, label date 2025-10-10) is for ORAL TABLETS, a different route and presentation, and its paediatric section covers only patients weighing at least 50 kg - it supplies no intravenous paediatric regimen either.

Dose adjustments

Renal

Contraindicated in moderate to severe renal impairment (glomerular filtration rate below 20 ml/min) and in severe or acute liver failure. A dose reduction may be appropriate in elderly patients and in patients with hypothyroidism, renal disease and chronic hepatic disease.

Dose auto-extracted from UK Summary of Product Characteristics (SPC) via the eMC; US FDA prescribing information (openFDA / DailyMed) — cross-check; US labelling may differ from UK — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

  • Hypersensitivity to morphine, to other opioid preparations or to any of the excipients
  • Respiratory depression; obstructive airways disease; excessive bronchial secretions; during a bronchial asthma attack; heart failure secondary to chronic lung disease
  • Head injury; raised intracranial pressure; coma; convulsion disorders
  • Ulcerative colitis; risk of paralytic ileus; biliary and renal tract spasm; acute alcoholism; phaeochromocytoma
  • Moderate to severe renal impairment (glomerular filtration rate below 20 ml/min); severe or acute liver failure
  • Patients receiving monoamine oxidase inhibitors, or within two weeks of discontinuing such treatment
  • Use during pregnancy or lactation is not recommended

Side effects

  • Respiratory depression (high doses may produce respiratory depression and hypotension with deepening coma); inhibition of the cough reflex; central sleep apnoea syndrome
  • Nausea, vomiting and constipation - with long-term use these generally lessen, although constipation frequently persists
  • Drowsiness, confusion, dizziness, headache, euphoria or dysphoria, sleep disturbance, hallucinations, delirium, agitation; seizures (convulsions may occur particularly in infants)
  • Orthostatic hypotension, hypotension, hypertension, bradycardia, tachycardia, palpitations, syncope, facial flushing, oedema
  • Drug dependence, tolerance and drug withdrawal syndrome; long-term use is associated with hyperalgesia, adrenal insufficiency and hypogonadism
  • Urinary retention, difficult micturition, ureteric spasm; biliary spasm and spasm of the sphincter of Oddi; pruritus, rash, urticaria; pain and irritation at the injection site

Interactions

  • Monoamine oxidase inhibitors - contraindicated during treatment and within two weeks of discontinuing them (eMC section 4.3)
  • Other opioid analgesics such as codeine, given orally or by any other route - increase the CNS depressant effect of morphine (eMC section 4.4)
  • Benzodiazepines and related sedative medicines - concomitant use may result in sedation, respiratory depression, coma and death; reserve concomitant prescribing for patients with no alternative treatment options, use the lowest effective dose for the shortest possible duration, and follow patients closely for respiratory depression and sedation (eMC section 4.4)
  • Benzodiazepines and other CNS depressants including alcohol, sedatives/hypnotics, anxiolytics, tranquilizers, muscle relaxants, general anaesthetics, antipsychotics and other opioids - additive pharmacologic effect increasing the risk of hypotension, respiratory depression, profound sedation, coma and death; consider prescribing naloxone for emergency treatment of opioid overdose if concomitant use is warranted (US labelling section 7)
  • Serotonergic drugs - concomitant use of opioids with drugs affecting the serotonergic neurotransmitter system has resulted in serotonin syndrome (US labelling section 7, truncated at the source-fetch limit)
  • NOTE: eMC section 4.5 was not captured in this bundle; the items marked (US labelling) come from the US prescribing information for morphine sulfate ORAL TABLETS and should be checked against the UK SPC

Clinical monograph

How it works

It is an agonist at mu-opioid receptors in the central nervous system, inhibiting ascending nociceptive transmission and altering the perception of and response to pain.

Prescribing in practice

  • Titrate to effect with close observation for respiratory depression and sedation, monitoring oxygen saturation and conscious level, and have naloxone available.
  • Burns produce dynamic and often escalating pain with hyperalgesia and opioid tolerance, so requirements may be high and are best managed within a multimodal regimen and on a background-plus-procedural model.
  • Active metabolites accumulate in renal impairment, so reduce frequency and monitor more closely when renal function is reduced, which is common in major burns.

Monitoring

Monitor pain scores, respiratory rate, sedation and oxygen saturation during titration, with continuous observation for procedural dosing.

Counselling the patient

  • This strong painkiller will be adjusted to your pain and monitored closely.
  • Tell staff if you feel very drowsy, sick or short of breath.
  • Constipation is common and laxatives are usually given alongside.

Evidence & guidelines

Opioids including morphine are recommended as core burns analgesia by burn-care guidance, used within a multimodal, procedural-and-background framework.

Reference: British Burns Association Analgesia Guidelines; ANZBA Burns Guidelines; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Related

Curated clinical cross-links plus same-class fallbacks.

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