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Mannitol parenteral

Updated 2 Feb 2023 | Osmotic diuretics


Infusions of mannitol.

Drugs List

  • mannitol 10% infusion
  • mannitol 15% infusion
  • mannitol 20% infusion
  • Therapeutic Indications


    Acute renal failure (oliguric phase): prophylaxis/treatment
    Forced diuresis for increased excretion of toxic substances
    Osmotic diuresis
    Reduction of intracranial pressure
    Treatment of cerebral oedema
    Urgent and/or pre-operative reduction of elevated intraocular pressure



    Acute renal failure
    Between 50g to 200g in a 24 hour period may be given. An adequate response is usually observed with approximately 100g per 24 hours.
    Maximum single dose: 50g.
    Maximum daily dose: 200g.

    The rate of infusion is usually adjusted to maintain a urine flow of at least 30ml/hour to 50ml/hour. Only in emergency situations, the maximum infusion rate can be as high as 200mg/kg infused over 5 minutes. After 5 minutes, the infusion rate should be readjusted to maintain a urine flow of 30ml/hour to 50ml/hour, with a maximum dose of 200g/24 hours.

    Use in patients with marked oliguria or suspected inadequate renal function
    Test dose: Approximately 200mg/kg over a period of 3 to 5 minutes. The response to the test dose is considered adequate if at least 30ml/hour to 50ml/hour of urine is excreted for 2 to 3 hours.
    If adequate response is not attained, a further test dose may be given. If an adequate response to the second test dose is not attained, treatment with mannitol should be discontinued and the patient reassessed as established renal failure may be present.

    Reduction of intracranial pressure, cerebral volume and intraocular pressure
    1.5g/kg to 2g/kg, given over a period of 30 to 60 minutes.
    If mannitol is being given as a preoperative treatment the dose should be administered 1 to 1.5 hours prior to surgery, to obtain the maximum effect.

    The following alternative dosing schedule may be suitable:
    0.25g/kg to 2g/kg. This dose may be repeated once or twice, after an interval of 4 to 8 hours, if necessary.

    Renal failure prophylaxis
    50g to 100g, given during cardiovascular and other types of surgery to help prevent acute renal failure. The concentration and volume will depend on the fluid requirements of the patient.

    Promotion of elimination of renally excreted toxic substances in poisoning
    Initial loading dose: 25g.
    In induction of forced diuresis in the adjunctive treatment of severe drug intoxications, the dose of mannitol should be adjusted to maintain urinary output of at least 100ml/hour and positive fluid balance of 1 to 2 litres.


    In renal insufficiency
    Test dose: 200mg/kg over 3 to 5 minutes.
    Treatment dose: 0.5g/kg to 1.5g/kg. This dose may be repeated once or twice, after an interval of 4 to 8 hours, if necessary. Reduction of cerebral oedema, intracranial pressure and intraocular pressure
    Treatment dose: 0.5g/kg to 1.5g/kg, to be given over 30 to 60 minutes. This dose may be repeated once or twice, after an interval of 4 to 8 hours, if necessary.

    The following alternative dosing schedule may be suitable:

    Peripheral oedema and ascites (unlicensed)
    1g/kg to 2g/kg, given over 2 to 6 hours.

    Cerebral oedema (unlicensed)
    Children aged 12 to 18 years
    0.25g/kg to 2g/kg, by intravenous infusion over 30 to 60 minutes. This dose may be repeated once or twice, after an interval of 4 to 8 hours, if necessary.

    Children aged 1 month to 12 years
    0.25g/kg to 1.5g/kg, by intravenous infusion over 30 to 60 minutes. This dose may be repeated once or twice, after an interval of 4 to 8 hours, if necessary.

    Patients with Renal Impairment

    Patients should be give a test dose prior to treatment as they are more susceptible to adverse events (See Dosage; Adult).


    For intravenous infusion only.


    No response to test dose
    Pulmonary oedema
    Renal failure with anuria
    Severe cardiac failure
    Severe dehydration

    Precautions and Warnings

    Predisposition to hypovolaemia
    Cardiac impairment
    Intracranial haemorrhage
    Severe renal impairment

    May obscure/intensify inadequate hydration
    Evaluate patients for cardiovascular disease prior to treatment
    Avoid rapid infusion rates
    Do not mix with whole blood
    Examine solution for crystals before use- redissolve if necessary
    High doses in large volumes may cause water intoxication/hyponatraemia
    If extravasation occurs follow local policy & seek expert help immediately
    Perform test dose to determine adequate response
    May aggravate pre-existing haemoconcentration
    Monitor cardiac function
    Monitor central venous pressure
    Monitor fluid and electrolyte status
    Monitor pulmonary function regularly
    Monitor renal function
    Monitor serum osmolarity
    Monitor urine output
    May exacerbate existing or latent congestive cardiac failure
    May affect results of some laboratory tests
    Discontinue if hypersensitivity reactions occur
    Discontinue in the event of progressive cardiac failure
    Discontinue in the event of progressive deterioration in pulmonary function
    Discontinue in the event of progressive renal damage

    Mannitol solution may crystallise during storage. Storing the solution between 20 and 30 degrees C helps prevent this. However carefully examine solution for crystals immediately before use. Crystals can be redissolved by raising the temperature to 60 degrees C and shaking occasionally. Cool to blood temperature before use.

    Mannitol may open the blood-brain barrier at high doses, resulting in a rebound increase in intracranial pressure.
    Mannitol is not recommended in intracranial bleeding except during craniotomy.

    Pregnancy and Lactation


    Use mannitol with caution during pregnancy.

    There is extremely limited information about its use in pregnancy. Schaefer (2007) states that if an osmotic diuretic is required during pregnancy mannitol may be used, although diuretics are not part of the standard therapy for hypertension and oedema in pregnancy. Schaefer concludes that exposure to a diuretic is not an indication for interrupting the pregnancy.

    The use of all medication in pregnancy should be avoided whenever possible; particularly in the first trimester. Non-drug treatments should also be considered. When essential, a medication with the best safety record over time should be chosen, employing the lowest effective dose for the shortest possible time. Polypharmacy should be avoided. Teratogens taken in the pre-embryonic period, often quoted as lasting until 14 to 17 days post-conception, are believed to have an all-or-nothing effect. Where drugs have a short half-life, and when the date of conception is certain, this may allow women to be reassured where drug exposure has occurred within this time frame. Further advice may be available from the UK National Teratology Information Service (NTIS) and through ToxBase, available via password on the internet ( ) or if this is unavailable at the backup site ( ).


    Use mannitol with caution during breastfeeding.

    It is unknown if mannitol is excreted into human breast milk. Although there is no hard data, drawing on knowledge of mannitol and mother and infant physiology, one author suggests that passage into the milk is only likely in the first few days post partum, and considers passage into the breast milk likely to be minimal beyond 48 hours post-partum. Further, that oral absorption by the infant is likely to be minimal after the first few days post partum (when the gastrointestinal tract becomes less porous). Watery diarrhoea in the infant is a remote possibility. A reduction in the production of milk, from the osmotic diuretic effect is possible (Hale, 2010).

    Neonates, infants born prematurely, those with low birth weight, those with an unstable gastrointestinal function or who have serious illnesses may require special consideration. For any infant, if a drug is prescribed to the nursing mother, it should be at the lowest practical dose and for the shortest time. When drug administration is unavoidable and breastfeeding is to continue, minimisation of exposure of the infant to the drug may sometimes be achieved by timing the maternal doses to just after a feeding episode. Infants exposed to drugs via breast milk should be monitored for unusual signs or symptoms. Interactions between the drug received by the infant from the mother's milk and medication prescribed for the infant should also be considered, for example, when the drug given to the infant may prevent metabolism of the drug received via breast milk.
    Specialist advice is available from the UK Drugs in Lactation Advisory Service at

    Side Effects

    Acute renal failure
    Anaphylactic reaction
    Anaphylactic shock
    Arm pain
    Blurred vision
    Chest pain
    Circulatory disturbances
    Compartment syndrome
    Congestive cardiac failure
    Dry mouth
    Erythema at injection site
    Fluid and electrolyte disturbances
    Hypersensitivity reactions
    Inflammation (injection site)
    Itching (injection site)
    Local pain (injection site)
    Osmotic nephrosis
    Pulmonary oedema
    Raised intracranial pressure
    Rash at injection site
    Respiratory depression
    Skin necrosis
    Thrombophlebitis (injection site)
    Urinary retention

    Effects on Laboratory Tests

    Mannitol can cause false low results in some tests systems for inorganic phosphorus blood concentrations.
    Mannitol produces false positive results in tests for blood ethylene glycol concentrations in which mannitol is initially oxidized to an aldehyde.


    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: November 2014

    Reference Sources

    Drugs During Pregnancy and Lactation: Treatment Options and Risk Assessment, 2nd edition (2007) ed. Schaefer, C., Peters, P. and Miller, R. Elsevier, London.

    Drugs in Pregnancy and Lactation: A Reference Guide to Fetal and Neonatal Risk, 9th edition (2011) ed. Briggs, G., Freeman, R. and Yaffe, S. Lippincott Williams & Wilkins, Philadelphia.

    Martindale: The Complete Drug Reference, 37th edition (2011) ed. Sweetman, S. Pharmaceutical Press, London.

    Medications and Mothers' Milk, 14th Edition (2010) Hale, T. Hale Publishing, Amarillo, Texas.

    Summary of Product Characteristics: Mannitol 10% solution for infusion. Fresenius Kabi Ltd. Revised November 2014.
    Summary of Product Characteristics: Mannitol 20% solution for infusion. Fresenius Kabi Ltd. Revised November 2014.
    Summary of Product Characteristics: Mannitol 10% solution for infusion BP. Baxter Healthcare Ltd. Revised August 2012.
    Summary of Product Characteristics: Mannitol 15% solution for infusion. Baxter Healthcare Ltd. Revised January 2018.
    Summary of Product Characteristics: Mannitol intravenous infusion 20% w/v from Baxter Healthcare Ltd. Revised January 1996.

    NICE Evidence Services Available at: Last accessed: 23 November 2017

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