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Morphine sulfate intravenous (pca)

Updated 2 Feb 2023 | Opioid analgesics


Infusions of morphine sulfate for use in patient controlled analgesia (PCA) systems.

Drugs List

  • morphine sulfate 100mg/50ml solution for infusion vial
  • morphine sulfate 10mg/10ml solution for injection ampoule
  • morphine sulfate 50mg/50ml solution for infusion vial
  • morphine sulfate 5mg/5ml solution for injection ampoule
  • Therapeutic Indications


    Pain - moderate to severe

    Morphine sulfate injection is indicated for the relief of moderate to severe pain. Morphine sulfate injection is used especially in pain associated with cancer, myocardial infarction and surgery. Morphine also reduces the anxiety and insomnia which may be caused by severe pain.


    Specific analgesic requirements vary between patients and therefore individualised treatment strategies are required.

    The duration of treatment should be kept to a minimum, although dependence and tolerance are not usually a problem when morphine is used legitimately in patients with opioid-sensitive pain.


    Loading dose

    Typically between 1mg and 10mg (max. 15mg) by intravenous infusion over 4-5 minutes depending on the patients diagnosis and condition. Loading infusion times may vary amongst manufacturers.

    PCA demand dose

    Recommended demand doses vary between manufacturers from 1mg with a 5 to 10 minute lockout to 2.5 to 5mg with a 5 to 10 minute lockout. Dose will vary with loading dose, tolerance and condition of the patient and whether a background infusion of morphine is being given.

    Patients with Renal Impairment

    The Renal Dose Handbook suggests the following dose adjustments:

    Glomerular fraction rate 20 to 50ml/min: 75% of normal dose.


    For intravenous injection or intravenous infusion via a patient controlled analgesia (PCA) system.


    Acute abdomen
    Acute alcohol intoxication
    Children under 12 years
    Risk of paralytic ileus
    Within 2 weeks of discontinuing MAOIs
    Acute asthma
    Acute hepatic disorder
    Biliary tract spasm
    Cardiac failure secondary to pulmonary disorder
    Delayed gastric emptying
    Excessive bronchial secretions
    Head trauma
    Obstructive pulmonary disease
    Paralytic ileus
    Raised intracranial pressure
    Renal impairment - glomerular filtration rate below 20ml/minute
    Renal tract spasm
    Respiratory depression
    Severe hepatic impairment
    Ulcerative colitis

    Precautions and Warnings

    Post operatively
    Adrenal insufficiency
    Benign prostatic hyperplasia
    Biliary tract disorder
    Cardiac arrhythmias
    Diabetes mellitus
    Drug misuse
    Gastrointestinal obstruction
    History of alcohol abuse
    History of drug misuse
    Inflammatory bowel disease
    Mild hepatic impairment
    Mild renal impairment
    Myasthenia gravis
    Opioid dependence
    Psychiatric disorder
    Severe cardiac failure
    Severe hypopituitarism
    Sickle cell disease
    Urethral stricture

    Reduce dose in hypothyroidism
    Reduce dose in patients with hepatic impairment
    Reduce dose in patients with renal impairment
    Sodium content of formulation may be significant
    Advise patient ability to drive or operate machinery may be impaired
    Advise patient not to drive until they know how the medicine affects them
    Advise patient this medicine is subject to driving restrictions
    If adrenal insufficiency occurs, consider corticosteroid cover
    Monitor patient's sedation level
    Monitor patients with a history of alcoholism and drug abuse
    Neonate exposed in utero: Monitor for neonatal withdrawal syndrome
    Reassess need for continued treatment at regular intervals
    Tolerance and dependence may occur
    Consider dose reduction or change in opioid if evidence of hyperalgesia
    Potential for withdrawal symptoms
    Prolonged use at high doses may result in hyperalgesia
    Avoid abrupt withdrawal
    Reduce dose in elderly
    Advise that effects are potentiated by CNS depressants (including alcohol)

    Morphine sulfate injection should be used with caution post-operatively following total joint arthroplasty (colonic pseudo-obstruction).

    Before commencing treatment with morphine sulfate, a strategy should be constructed with the patient for ending treatment in order to reduce the risk of addiction and drug withdrawal syndrome.

    A full patient history should be established to document concomitant medications and past and present medical and psychiatric conditions. The risk of developing tolerance to morphine sulfate should be explained to the patient prior to treatment. All patients should be closely observed for signs of misuse, abuse or addiction. Patients at risk of opioid misuse may require additional support and monitoring.

    Monitor for pain, sedation and signs of respiration impairment during the first few hours of treatment.

    Long-term use of opioid analgesics may be associated with decreased sex hormone levels and increased prolactin.

    Due to possible association between acute chest syndrome (ACS) and morphine use in sickle cell disease, patients treated with morphine during a vaso-occlusive crisis, close monitoring for ACS is warranted.

    Pregnancy and Lactation


    Use morphine sulfate with caution during pregnancy.

    Regular use during pregnancy may cause drug dependence in the foetus, causing withdrawal symptoms in the neonate. Administration during labour may depress respiration in the neonate and an antidote for the child should be readily available. Animal studies have shown teratogenic effects. Human data is limited and as such a potential risk cannot be ruled out. Use of morphine sulfate via a Patient Controlled Analgesia (PCA) system is not recommended by some manufacturers.

    Schaefer (2015) indicates that morphine use during pregnancy should be limited to special situations where no safer alternatives are available. Tapering off the opioid should always be done gradually to prevent withdrawal symptoms in both the mother and the fetus.


    Use morphine sulfate with caution in breastfeeding.

    The manufacturer does not recommend the use of morphine sulfate injection during breastfeeding as morphine may be secreted in breast milk and cause respiratory depression in the infant. A decision must be made whether to discontinue breastfeeding or to discontinue/abstain from morphine therapy taking into account the benefit of breastfeeding for the child and the benefit of therapy for the woman.

    Lactmed (2021) indicates that once the mother starts breastfeeding, it is best to provide pain control with a nonnarcotic analgesic and limit maternal intake of morphine to a 2 to 3 days at a low dosage with close infant monitoring, especially in the outpatient setting. If the baby shows signs of increased sleepiness (more than usual), difficulty breastfeeding, breathing difficulties, or limpness, medical help should be sought immediately.

    Effects on Ability to Drive and Operate Machinery

    This class of medicine is in the list of drugs included in regulations under 5a of the Road Traffic Act 1988 (England and Wales). This medicine may be subject to police testing and has specified maximum blood levels for driving. When prescribing this medicine: Advise patient the medicine can affect cognitive function and is likely to affect ability to drive. Advise patient not to drive until they know how the medicine affects them. It is an offence to drive while under the influence of this medicine. However, a patient is not committing an offence (called 'statutory defence') if: 1.The medicine has been prescribed to treat a medical or dental problem and 2.The medicine has been taken according to the instructions given by the prescriber and/or in the information provided with the medicine and 3.The medicine was not affecting the ability to drive safely. For further guidance see

    Side Effects

    Abdominal pain
    Allergic reaction
    Biliary spasm
    Circulatory failure
    Contact dermatitis
    Cough suppression
    Difficulty in micturition
    Dry mouth
    Elevation of liver enzymes
    Erectile dysfunction
    Exacerbation of pancreatitis
    Facial flushing
    Local pain (injection site)
    Mood changes
    Muscle rigidity
    Orthostatic hypotension
    Paralytic ileus
    Pulmonary oedema
    Raised intracranial pressure
    Reduced libido
    Reduction of male potency
    Renal failure
    Respiratory depression
    Sexual dysfunction
    Sleep disturbances
    Taste disturbances
    Ureteric spasm
    Urinary retention
    Visual disturbances
    Withdrawal symptoms

    Withdrawal Symptoms and Signs

    Some or all of the opioid drug withdrawal syndrome side effects are: restlessness, lacrimation, rhinorrhoea, yawning, perspiration, chills, myalgia, mydriasis and palpitations. Other symptoms may also develop including irritability, agitation, anxiety, hyperkinesia, tremor, weakness, insomnia, anorexia, abdominal cramps, nausea, vomiting, diarrhoea, increased blood pressure, increased respiratory rate or heart rate.

    When a patient no longer requires treatment, it is advisable to taper the dose gradually to minimise symptoms of withdrawal. Tapering from a high dose may take weeks to months.


    It is strongly recommended that the UK National Poisons Information Service be consulted on cases of suspected or actual overdose where there is doubt over the degree of risk or about appropriate management.

    The following number will direct the caller to the relevant local centre (0844) 892 0111

    Information may be obtained if you have access to ToxBase the primary clinical toxicology database of the National Poisons Information Service. This is available via password on the internet ( ) or if this is unavailable at the backup site ( ).

    Further Information

    Last Full Review Date: October 2021

    Reference Sources

    Drugs During Pregnancy and Lactation: Treatment Options and Risk Assessment, 3rd edition (2015) ed. Schaefer, C., Peters, P. and Miller, R. Elsevier, London.

    The Renal Drug Handbook. Fifth Edition (2019) ed. Ashley, C. and Dunleavy, A. Radcliffe Publishing Ltd, London.

    Summary of Product Characteristics: Morphine Sulfate Injection 1mg/ml. Aurum Pharmaceuticals Ltd. Revised April 2019.
    Summary of Product Characteristics: Morphine Sulfate Injection 1mg/ml. Torbay & South Devon NHS Foundation Trust. Revised April 2020.
    Summary of Product Characteristics: Morphine Sulfate Injection BP 2mg/ml. Martindale Pharma. Revised April 2019.
    Summary of Product Characteristics: Morphine Sulfate Solution for Injection 10mg/10ml. Hameln Pharma Ltd. Revised September 2020.

    NICE Evidence Services Available at: Last accessed: 06 October 2021 Government departments. Department for Transport. Publications. Drug driving and medicine: advice for healthcare professionals. Drug driving: Guidance for healthcare professionals on drug driving. Available at: Last accessed: 11 October 2021

    US National Library of Medicine. Toxicology Data Network. Drugs and Lactation Database (LactMed).
    Available at:
    Morphine. Last revised: 24 July 2021
    Last accessed: 06 October 2021

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