OSMITROL 10% IN WATER

Clinical safety rating: caution

Comprehensive clinical and safety monograph for OSMITROL 10% IN WATER (OSMITROL 10% IN WATER).

How it works

Osmotic diuretic that increases plasma osmolality, drawing water from intracellular spaces into extracellular fluid and increasing renal blood flow, thereby enhancing water excretion.

What the body does with it

Metabolism	Primarily excreted unchanged in urine; minimal hepatic metabolism.
Excretion	Renal: >90% excreted unchanged by glomerular filtration with minimal tubular reabsorption. Negligible biliary/fecal elimination.
Half-life	Terminal elimination half-life is approximately 0.25–1.5 hours in patients with normal renal function, prolonged in renal impairment.
Protein binding	Negligible (<1%); mannitol does not bind significantly to plasma proteins.
Volume of Distribution	Approximately 0.5–0.7 L/kg; distributes primarily in extracellular fluid, excluded from intracellular space and does not cross blood-brain barrier under normal conditions.
Bioavailability	Intravenous: 100% bioavailability. Not administered via other routes; oral bioavailability is poor (~17%) due to limited gastrointestinal absorption.
Onset of Action	Intravenous: Diuresis begins within 1–3 hours after infusion. Reduction of intracranial pressure occurs within 15 minutes, maximal effect at 60–90 minutes.
Duration of Action	Diuresis persists for 6–8 hours post-infusion. Reduction of intracranial pressure lasts approximately 3–6 hours, with rebound effect possible after cessation.

Classification & Brands

Dosing & administration

0.25-2 g/kg intravenously over 30-60 minutes, repeated every 6-12 hours as needed. Maximum dose: 2 g/kg per dose or 200 g daily.

Dosage form	INJECTABLE
Renal impairment	Contraindicated in anuria or severe renal impairment (GFR < 10 mL/min). For GFR 10-50 mL/min: reduce dose by 50% and monitor serum osmolality. For GFR > 50 mL/min: no adjustment needed.
Liver impairment	No specific adjustment for Child-Pugh classes; use with caution in severe hepatic impairment due to risk of fluid overload.
Pediatric use	0.25-1 g/kg intravenously over 30-60 minutes, repeated every 6-12 hours. Maximum 2 g/kg per dose.
Geriatric use	Start at lower end of dosing range (0.25-0.5 g/kg) due to age-related decline in renal function; monitor serum electrolytes and osmolality closely.

Use during pregnancy

1st trimester	Consult provider
2nd trimester	Consult provider
3rd trimester	Consult provider

Clinical note

Comprehensive clinical and safety monograph for OSMITROL 10% IN WATER (OSMITROL 10% IN WATER).

Breastfeeding	Not known if mannitol is excreted in human breast milk. Due to its molecular weight and water solubility, excretion is possible but likely low. Use with caution; consider risk-benefit. M/P ratio: not available.
Teratogenic Risk	Osmotic diuretics like mannitol cross the placenta. First trimester: limited human data, but animal studies show no consistent teratogenicity. Second and third trimesters: may cause fetal fluid and electrolyte disturbances, including hyponatremia and dehydration. Caution advised; avoid for prolonged use or high doses. Fetal monitoring recommended.

Warnings & precautions

■ FDA Black Box Warning

None

Side Effect Profile

Serious Effects

Absolute Contraindications

["Anuria due to severe renal disease","Severe pulmonary congestion or pulmonary edema","Active intracranial bleeding (except during craniotomy)","Severe dehydration","Hypersensitivity to mannitol"]

Clinical Precautions

Precautions

["May cause fluid and electrolyte imbalances","Risk of pulmonary congestion or edema in patients with impaired cardiac function","Monitor renal function and serum electrolytes","Avoid extravasation due to risk of local tissue damage"]

Clinical Tips & Counseling

Drug interactions

Loading safety data…

OSMITROL 10% IN WATER

Clinical safety rating: caution

Comprehensive clinical and safety monograph for OSMITROL 10% IN WATER (OSMITROL 10% IN WATER).

How it works

Osmotic diuretic that increases plasma osmolality, drawing water from intracellular spaces into extracellular fluid and increasing renal blood flow, thereby enhancing water excretion.

What the body does with it

Metabolism	Primarily excreted unchanged in urine; minimal hepatic metabolism.
Excretion	Renal: >90% excreted unchanged by glomerular filtration with minimal tubular reabsorption. Negligible biliary/fecal elimination.
Half-life	Terminal elimination half-life is approximately 0.25–1.5 hours in patients with normal renal function, prolonged in renal impairment.
Protein binding	Negligible (<1%); mannitol does not bind significantly to plasma proteins.
Volume of Distribution	Approximately 0.5–0.7 L/kg; distributes primarily in extracellular fluid, excluded from intracellular space and does not cross blood-brain barrier under normal conditions.
Bioavailability	Intravenous: 100% bioavailability. Not administered via other routes; oral bioavailability is poor (~17%) due to limited gastrointestinal absorption.
Onset of Action	Intravenous: Diuresis begins within 1–3 hours after infusion. Reduction of intracranial pressure occurs within 15 minutes, maximal effect at 60–90 minutes.
Duration of Action	Diuresis persists for 6–8 hours post-infusion. Reduction of intracranial pressure lasts approximately 3–6 hours, with rebound effect possible after cessation.

Classification & Brands

Dosing & administration

0.25-2 g/kg intravenously over 30-60 minutes, repeated every 6-12 hours as needed. Maximum dose: 2 g/kg per dose or 200 g daily.

Dosage form	INJECTABLE
Renal impairment	Contraindicated in anuria or severe renal impairment (GFR < 10 mL/min). For GFR 10-50 mL/min: reduce dose by 50% and monitor serum osmolality. For GFR > 50 mL/min: no adjustment needed.
Liver impairment	No specific adjustment for Child-Pugh classes; use with caution in severe hepatic impairment due to risk of fluid overload.
Pediatric use	0.25-1 g/kg intravenously over 30-60 minutes, repeated every 6-12 hours. Maximum 2 g/kg per dose.
Geriatric use	Start at lower end of dosing range (0.25-0.5 g/kg) due to age-related decline in renal function; monitor serum electrolytes and osmolality closely.

Use during pregnancy

1st trimester	Consult provider
2nd trimester	Consult provider
3rd trimester	Consult provider

Clinical note

Comprehensive clinical and safety monograph for OSMITROL 10% IN WATER (OSMITROL 10% IN WATER).

Breastfeeding	Not known if mannitol is excreted in human breast milk. Due to its molecular weight and water solubility, excretion is possible but likely low. Use with caution; consider risk-benefit. M/P ratio: not available.
Teratogenic Risk	Osmotic diuretics like mannitol cross the placenta. First trimester: limited human data, but animal studies show no consistent teratogenicity. Second and third trimesters: may cause fetal fluid and electrolyte disturbances, including hyponatremia and dehydration. Caution advised; avoid for prolonged use or high doses. Fetal monitoring recommended.

Warnings & precautions

■ FDA Black Box Warning

None

Side Effect Profile

Serious Effects

Absolute Contraindications

["Anuria due to severe renal disease","Severe pulmonary congestion or pulmonary edema","Active intracranial bleeding (except during craniotomy)","Severe dehydration","Hypersensitivity to mannitol"]