Mannitol
OSMITROL
“Osmotic controllin’ Manatee”
decreases serum lithium
What it isOsmotic diuretic drawing water from tissue into plasma; raised intracranial pressure and glaucoma.
Why this oneUnlike hypertonic saline, it draws brain water without adding sodium but causes osmotic diuresis.
What limits itRebound intracranial pressure once the blood-brain barrier is disrupted. It must be filtered for crystals; watch osmolar gap and renal function.
FDA-approved for
- cerebral edema/oliguria (~1964)
FDA label
Read the full label on DailyMed ↗
| FDA dosing | Population | Start | Target | Max |
|---|---|---|---|---|
| Reduction of intracranial pressure / cerebral edema | Adults | 0.25 g/kg IV over 30 minutes | 0.25 g/kg, may repeat every six to eight hours | Undefined |
| Reduction of elevated intraocular pressure | Adults | 1.5–2 g/kg IV once over ≥30 minutes (20%: 7.5–10 mL/kg; 15%: 10–13 mL/kg) | Single dose; pre-op give sixty to ninety minutes before surgery | 2 g/kg single dose |
| Reduction of intracranial or intraocular pressure | Pediatric | Approved; optimal pediatric dose not defined | Undefined | Undefined |
Renal Contraindicated in anuria; pre-existing renal disease or nephrotoxic drugs/diuretics ↑ renal-failure risk — evaluate before use, discontinue if renal function worsens
Hepatic Undefined
Dose, concentration and rate individualized to age, weight, fluid/electrolyte status, serum osmolality, urine output. Monitor serum osmolarity, electrolytes, osmol gap, renal/cardiac/pulmonary function and ICP during and after infusion.
Instructions
- IV infusion, preferably into a large central vein (≥10% peripheral → phlebitis)
- Evaluate renal, cardiac, pulmonary status and correct fluid/electrolyte imbalances before giving
- Use administration set with final in-line filter; inspect for crystals — re-dissolve by warming up to 70°C (not water bath or microwave), cool before use
- Do not give through same set as blood products; do not admix
- Prevent air embolism: non-vented set, no series connections, do not pressurize bag; single use
Available strengths
- powder 40 mg
- inj 250 mg/mL
Contraindications
- Anuria
- Severe hypovolemia
- Pre-existing severe pulmonary vascular congestion or pulmonary edema
- Active intracranial bleeding (except during craniotomy)
Cautions
- Hypersensitivity reactions incl. anaphylaxis
- Renal complications incl. renal failure
- CNS toxicity (confusion, lethargy, coma; rebound ICP)
- Fluid and electrolyte imbalances, hyperosmolarity
- Monitoring / laboratory tests
- Infusion site reactions (extravasation, compartment syndrome)
- Interference with lab tests (false-low phosphorus, false-positive ethylene glycol)
Adverse reactions
- Hypersensitivity reactions
- Renal failure
- CNS toxicity
- Hypo/hypervolemia
- Hypo/hypernatremia
- Hypo/hyperkalemia
- Infusion site reactions
Pregnancy Decades of case data show no drug-associated risk of birth defects or miscarriage; crosses placenta and may cause fetal fluid shifts.
Lactation No data on presence in human or animal milk; weigh breastfeeding benefits against maternal need.
Cost
| Strength | #/mo | generic $/unit | CostPlus | |
|---|---|---|---|---|
| 250 mg/mL | inj | per unit | not offered | |
| 40 mg | powder | per unit | not offered |
Available combined with: sorbitol
Generic entry1982
NO BOXED WARNINGS
Principal riskRebound intracranial pressure; watch the osmolar gap
Classes and tags
Clinical profile
Legacy pregnancy categoryC
Defining liabilityDiarrhea, dehydration and electrolyte disturbance, especially with excessive or prolonged use.
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