Mannitol Intravenous for Adults

Who can administer

May be administered by registered competent doctor or nurse/midwife

Only the 10% solution is now available for ADULT patients. (The 20% solution is stocked for use in paediatric patients)
Crystallisation may occur - see under 'storage requirements' for further information
See 'Monitoring requirements' below
Flush line with Glucose 5% as there is a risk of precipitation with Sodium chloride 0.9% ^{(ref 1)}
Administer via central line or large peripheral vein
Extravasation causes inflammation and thrombophlebitis

Mannitol 10% 500mL infusion (50g in 500mL)

Already in solution

Not required - product ready for infusion

Slow intravenous injection (test dose for patients with marked oliguria or suspected inadequate renal function)

Intermittent intravenous infusion (administer using an electronically controlled infusion device)

See under 'dose' for details
Administer via a giving set that incorporates a 15 micron in-line filter ^{(ref 1)} - check packaging of administration set for details)

Volume in ml of Mannitol 10% solution required
Required dose	15g	25g	50g	75g	100g	150g
10% solution	150ml	250ml	500ml	750ml	1000ml	1500ml

Reduction of intracranial pressure, cerebral volume and intraocular pressure

Usual dose: 15 to 20mL/kg (10% infusion) administered over 30 to 60 minutes (some references suggest a range of 2.5 to 20mL/kg ^{(ref 2)})
Dose may be repeated once or twice after 4 to 8 hours ^{(ref 2)}
When used pre-operatively, the dose should be administered 60 to 90 minutes before surgery to obtain the maximum effect

Use in patients with oliguria or renal impairment

A test dose (to assess renal function) of about 2mL per kg (10% infusion) should be administered over three to five minutes - this should produce a diuresis of at least 30 to 50ml/hour during the next two to three hours
A second test dose may be given if there is inadequate response to the first test dose
If the second test dose does not produce an adequate urine output, then need to reassess management

Promotion of elimination of renally excreted toxic substances in poisoning

An initial loading dose of 250mL (10% infusion) may be given
Adjust dose to maintain urinary output of at least 100mL/hour and positive fluid balance of 1 to 2 litres

Renal impairment

Use with caution in severe renal impairment
If the second test dose does not produce adequate urine output, reassess options

Store between 20 and 30⁰C ^{(ref 1)}
Do not refrigerate or freeze^{(ref 1)}
Solutions may crystallise, especially if stored at low temperatures
The administration set should contain a 15 micron in-line filter - see under method of administration above

Crystals may be redissolved by warming before use as follows:

Re-dissolve any crystals by warming to 37⁰C (Baxter products), or 60⁰C (Fresenius Kabi products)^{(ref 1)}
Use of dry heat (eg warming cabinet) is recommended - solutions should not be heated in water due to risk of contamination
Gently agitate occasionally^{(ref 1)}
Microwave heating should not be used
The product should be allowed to cool to 37⁰C before infusion

SPC March 2019

1. Injectable medicines administration guide, Medusa Accessed online 31/03/2026

2. BNF- accessed online 31/03/2026

Osmotic diuretic