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Strong Opioid Analgesic Pregnancy: SPC section 4.6, verbatim: 'Regular use during pregnancy may cause drug dependence in the foetus, leading to withdrawal symptoms in the neonate. If opioid use is required for a prolonged period in a pregnant woman, advise the patient of the risk of neonatal opioid withdrawal syndrome and ensure that appropriate treatment will be available. There are no adequate data from the use of morphine in pregnant women. Studies in animals have shown reproductive toxicity. Morphine Sulfate 1 mg/ml solution for injection is not, therefore, recommended for use in pregnancy. 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 signs of neonatal withdrawal (abstinence) syndrome.' Breast-feeding: 'Administration to nursing women is not recommended as morphine may be secreted in breast milk and may cause respiratory depression in the infant.' Fertility: 'Animal studies have shown that morphine may reduce fertility.' Section 4.3 additionally states that use during pregnancy or lactation is not recommended.

Morphine (IV/IM — Anaesthesia/ICU)

Brand names: Morphine Sulfate (generic), Sevredol (oral), Oramorph (oral)

Used in: Acute Coronary Syndrome & Chest Pain Burns

Morphine is a strong opioid for moderate-to-severe acute pain (including peri-operative and intensive care) and in palliative care; it is a controlled drug.

Adult dose

Dose: Acute pain by intravenous patient-controlled analgesia (PCA) — adults and children over 12 years. Loading dose typically between 1 mg and 10 mg (maximum 15 mg) of morphine sulfate given by intravenous infusion over four or five minutes, the dose chosen according to the patient's diagnosis and condition; then an initial PCA demand dose of 1 mg with a lockout period of 5 to 10 minutes. Dosages may vary depending on the loading dose, the tolerance and condition of the patient, and whether a background infusion of morphine is being given. SCOPE: this is the intravenous PCA regimen only — the source product is licensed and formulated for IV PCA, and its posology states no intramuscular dose, no oral dose and no continuous ICU infusion rate.
Route: Intravenous only. SPC posology, verbatim: 'For intravenous injection. The product should not be diluted before use. The medicinal product is to be visually inspected prior to use. Only clear solutions practically free from particles should be used.' PCA 'must only be carried out in departments and by staff who are trained and have experience of the system', patient selection 'must ensure that the patient is capable of understanding and following the instructions of the medical/nursing staff', and 'the specific department or unit protocols must be covered to ensure aseptic transfer of the contents of the vial to the PCA system'.
Frequency: Loading dose given once, by intravenous infusion over four to five minutes; thereafter the 1 mg demand dose is delivered on patient demand with a lockout period of 5 to 10 minutes. 'The duration of treatment should be kept to a minimum.'
Max: 15 mg — the maximum intravenous LOADING dose. SPC posology, verbatim: '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.' This source states no daily ceiling, no maximum cumulative PCA dose and no maximum demand dose — none is asserted here.
The recovered UK product is an intravenous morphine presentation for PCA, so it matches the page's primary route and indication (acute severe pain) but covers only the IV PCA subset of the page's routes — that scope is stated inside the dose text above, as required. No IM or oral figure has been taken from anywhere. || VERBATIM (SPC posology, adults and children over 12 years): 'Morphine Sulfate 1 mg/ml solution for injection is formulated for use by the intravenous route in Patient Controlled Analgesia (PCA) systems. ... There is a considerable variation in analgesic requirements among patients and therefore individualised treatment strategies are required. Dosage should be based on the severity of the pain and the response and opiate tolerance of the patient.' LOADING DOSE, verbatim: '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 used will depend upon the patient's diagnosis and condition.' PCA DEMAND DOSE, verbatim: 'An initial demand dose of 1 mg Morphine Sulfate 1 mg/ml solution for injection with a lockout period of 5 to 10 minutes is recommended. Dosages may vary depending on the loading dose, the tolerance and condition of the patient, and whether a background infusion of morphine is being given.' || EARLY MONITORING, verbatim: 'The patient should be specifically monitored for pain, sedation and respiratory rate during the first few hours of treatment to ensure that the dosage regimen is suitable.' || DISCONTINUATION, verbatim: 'An abstinence syndrome may be precipitated if opioid administration is suddenly discontinued. Therefore the dose should be gradually reduced prior to discontinuation.' Before starting, 'a discussion should be held with patients to put in place a strategy for ending treatment with morphine in order to minimise the risk of addiction and drug withdrawal syndrome'. A treatment strategy including duration, goals and an end-of-treatment plan should be agreed with the patient, with frequent physician-patient contact to evaluate the need for continued treatment; the product 'should not be used longer than necessary'. || ELDERLY, verbatim: 'Morphine doses need to be reduced in elderly patients.' || PAEDIATRIC — paedDose is null because this product carries no paediatric dose. Verbatim: 'Use in children: Not recommended for children under 12 years.' || NOT IN THIS BUNDLE: no intramuscular dose, no oral morphine posology, no continuous background/ICU infusion rate in mg/h, no opioid conversion ratios, and no dose for the under-12s. Some sections of the product information we used were incomplete — check the full SPC.

Dose adjustments

Renal

Moderate to severe renal impairment (glomerular filtration rate < 20 ml/min) is a CONTRAINDICATION for this product (section 4.3). Section 4.4 adds, verbatim: 'As with other narcotics, a dose reduction may be appropriate in elderly patients, in patients with hypothyroidism, renal and chronic hepatic disease.'

Hepatic

Severe or acute liver failure is a CONTRAINDICATION for this product (section 4.3). Section 4.4, verbatim: 'a dose reduction may be appropriate in elderly patients, in patients with hypothyroidism, renal and chronic hepatic disease.'

Dose independently re-sourced from UK Summary of Product Characteristics (SPC) via the eMC; US FDA prescribing information (openFDA / DailyMed) — cross-check; US labelling may differ from UK — clinician-reviewed. Always confirm against the product SmPC and your local formulary before prescribing.

US labelling (FDA)

Reference — US labelling, may differ from UK

Morphine sulfate tablets should be prescribed only by healthcare professionals who are knowledgeable about the use of opioids and how to mitigate the associated risks. ( 2.1 ) Use the lowest effective dosage for the shortest duration of time consistent with individual patient treatment goals. Reserve titration to higher doses of morphine sulfate tablets for patients in whom lower doses are insufficiently effective and in whom the expected benefits of using a higher dose opioid clearly outweigh the substantial risks. ( 2.1 , 5 ) Many acute pain conditions (e.g., the pain that occurs with a number of surgical procedures or acute musculoskeletal injuries) require no more than a few days of an …

Source: US FDA prescribing information (openFDA / DailyMed), label dated 2025-10-10. Accessed 2026-06-12. US dosing and indications can differ from UK practice — use UK sources for prescribing decisions.

Contraindications

  • Hypersensitivity to the active substance, to other opioid preparations or to any of the excipients
  • Respiratory depression; obstructive airways disease; excessive bronchial secretions; during a bronchial asthma attack; or heart failure secondary to chronic lung disease
  • Head injury; raised intra-cranial pressure
  • Coma
  • Convulsion disorders
  • Ulcerative colitis
  • Presence of a risk of paralytic ileus
  • Biliary and renal tract spasm
  • Acute alcoholism
  • Phaeochromocytoma
  • Moderate to severe renal impairment (glomerular filtration rate < 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 (section 4.3)

Side effects

  • Most common with morphine and other opioids (section 4.8, verbatim): 'respiratory depression, nausea, vomiting, constipation, drowsiness and confusion. With long term use these symptoms generally lessen, although constipation frequently persists.'
  • Psychiatric: drug dependence, restlessness, mood changes, hallucinations, delirium, disorientation, excitation, agitation, sleep disturbance
  • Nervous system: headache, vertigo, euphoria, dysphoria, dizziness, taste disturbances, seizures, paraesthesia, raised intracranial pressure, hyperhidrosis; allodynia and hyperalgesia have been reported
  • Cardiac and vascular: bradycardia, tachycardia, palpitations, syncope; orthostatic hypotension, hypotension, hypertension, facial flushing, oedema
  • Respiratory: bronchospasm (in association with anaphylaxis), inhibition of the cough reflex, central sleep apnoea syndrome
  • Gastrointestinal and hepatobiliary: dyspepsia, paralytic ileus, abdominal pain, anorexia, dry mouth, pancreatitis; biliary spasm and spasm of the sphincter of Oddi
  • Immune: anaphylactic and anaphylactoid reactions to morphine have been reported rarely
  • Endocrine: long term use of opioid analgesics can cause adrenal insufficiency; exacerbation of pancreatitis; long term use can cause hypogonadism in both men and women, leading to amenorrhoea, reduced libido, infertility, depression and erectile dysfunction
  • Eye and ear: visual disturbances, nystagmus, miosis; vertigo
  • Musculoskeletal: muscle fasciculation, myoclonus, rhabdomyolysis, muscle rigidity
  • Renal and urinary: difficult micturition, ureteric spasm, urinary retention
  • General: hypothermia, malaise, asthenia, pain and irritation at the injection site
  • Long-term use: abnormal pain sensitivity (hyperalgesia), tolerance, psychological and physical dependence, decreased potency; 'High doses may produce respiratory depression and hypotension, with deepening coma. Convulsions may occur particularly in infants.'
  • INCOMPLETE LIST — the section 4.8 text in this bundle ends at the source-fetch limit part-way through the drug dependence and withdrawal paragraph

Monitoring

  • Monitor pain, sedation and respiratory rate specifically during the first few hours of PCA treatment to confirm the dosage regimen is suitable (section 4.2).
  • Sedative co-prescription — section 4.4, verbatim: 'Concomitant use of morphine and sedative medicines such as benzodiazepines or related drugs may result in sedation, respiratory depression, coma and death.' If co-prescribed, use the lowest effective dose for the shortest time, follow the patient closely for respiratory depression and sedation, and inform patients and their caregivers to watch for these symptoms.
  • Sleep-related breathing disorders — 'Opioid use increases the risk of CSA in a dose-dependent fashion. In patients who present with CSA, consider decreasing the total opioid dosage.'
  • Opioid Use Disorder — assess risk (personal or family history of substance use disorder including alcohol, current tobacco use, or a personal history of other mental health disorders) before and during treatment; repeated use can lead to OUD even at therapeutic doses.
  • Frequent physician-patient contact to evaluate the need for continued treatment, consider discontinuation and adjust dosage; taper rather than stop abruptly.
  • Consider hyperalgesia, tolerance and progression of underlying disease if pain control is inadequate.
  • Monitor newborns of mothers given opioid analgesics in pregnancy for neonatal withdrawal (abstinence) syndrome (section 4.6).
  • No laboratory monitoring schedule is stated in the fetched sections — none is asserted here.

Clinical monograph

How it works

It is an agonist at opioid (mainly mu) receptors, reducing pain perception and transmission and producing dose-dependent respiratory depression.

Prescribing in practice

  • Constipation is almost universal — co-prescribe a laxative; nausea, sedation and itch are common.
  • Reduce the dose and lengthen intervals in renal impairment (active metabolites accumulate) and in older or frail patients; titrate to effect.
  • There is additive respiratory depression with other CNS depressants; naloxone reverses opioid effect in emergencies.

Monitoring

Monitor pain, sedation, respiratory rate and bowel habit; in acute or intravenous use observe closely for respiratory depression.

Counselling the patient

  • It commonly causes constipation — take the laxative provided.
  • It can cause drowsiness; do not drive while affected and avoid alcohol.
  • Take it only as prescribed; it can be habit-forming.

Evidence & guidelines

A strong opioid for severe acute pain and palliative care, used within opioid-stewardship principles and with attention to renal function.

Reference: RCoA Acute Pain Management Guidelines; Oxford Pain Group; MHRA on gabapentinoids + opioids; 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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