Mannitol

Contraindications

Hypersensitivity, anuria, severe pulmonary edema or heart failure, severe dehydration, metabolic edema, progressive renal dz, active intracranial bleeding (except during craniotomy)

Cautions

Do not mix w/ blood

May cause hypovolemia, headache, polydipsia

It might be more effective than pentobarbital, but less effective than hypertonic saline in pt w/acute traumatic brain injury

Half life: 100 min

Onset

Diuresis: 1-3 hr after IV administration of mannitol. Lowering of

IOP reduction: 30-60 min

ICP reduction: 15 min

Duration

IOP reduction: 4-6 hr

ICP reduction: 3-8 hr

Other Information

Metabolism: liver (very slight)

Metabolites: glycogen

Excretion: urine (80%)

Mechanism of Action

Osmotic diuretic

Mannitol is used in the treatment of:

• Brain Edema
• Ocular Hypertension

Mannitol is used in the prevention of:

• Oliguria

This medication may be prescribed for other uses. Ask your doctor or pharmacist for more information.

Mannitol may be found in some form under the following brand names:

• Osmitrol

• Resectisol

Tell your doctor about all the medicines you take including prescription and non-prescription medicines, vitamins, and herbal supplements. Especially tell your doctor if you take:

• MANNITOL/TOBRAMYCIN
• MANNITOL/ZOLEDRONIC ACID

This is not a complete list of Mannitoldrug interactions. Ask your doctor or pharmacist for more information.

Other drugs may interact with mannitol, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell each of your health care providers about all medicines you use now and any medicine you start or stop using.

An osmotic diuretic.a b

Contraindications

• In patients with well-established anuria caused by severe renal diseasea b or impaired renal function who do not respond to 2 test doses.a b (See Test Dose under Dosage and Administration.)

• Severe pulmonary congestion or frank pulmonary edema.a b

• Severe CHF.a

• Severe dehydration.a b

• Metabolic edema associated with capillary fragility or membrane permeability not associated with renal, cardiac, or hepatic disease.a

• Active intracranial bleeding except during craniotomy.a b

• Progressive renal disease or dysfunction, including increasing oliguria and azotemia, or progressive heart failure or pulmonary congestion occurring after institution of mannitol therapy.a b

Warnings/Precautions

Warnings

Risk of serious electrolyte disturbances (e.g., hyponatremia, hypernatremia, hypokalemia, hyperkalemia); may be severe enough to alter acid-base balance or depress respiration.a b Thiazides may be used if hypernatremia or hyperosmolality occurs.a

Accumulation of mannitol caused by inadequate urinary output or rapid administration of large doses may result in overexpansion of extracellular fluid and circulatory overload causing signs and symptoms of water intoxication.a Overhydration may be corrected by hemodialysis or administration of a potent diuretic (e.g., furosemide).a

If urine output declines during administration, review patient’s clinical status and discontinue mannitol if necessary.a

Stop or slow mannitol if central venous pressure rises or there is any other evidence of circulatory overload.a Fluid administration should not exceed 1 L/day in excess of urinary output.a

Sustained diuresis may result in intensification of preexisting hemoconcentration; also may result in hypovolemia which reduces glomerular filtration rate and enhances the reabsorption of sodium and water.a b

Prevent or treat volume and electrolyte depletion by administering dilute mannitol solutions with sodium chloride added or by alternating each liter of mannitol solution with a liter of sodium chloride injection to which 40 mEq of potassium chloride has been added.a If the threat of renal shutdown exists, potassium supplementation should be administered subsequent to, but not concomitantly with, mannitol.a

Overexpansion of extracellular fluid (see Fluid and Electrolyte Imbalance under Cautions) may result in pulmonary edema and fulminating CHF, especially in patients with diminished cardiac reserve.a b Carefully evaluate cardiovascular status prior to administration.b

Possible irreversible vacuolar nephrosis.a b

General Precautions

Possible pseudoagglutination if electrolyte-free mannitol solutions are given concomitantly with blood.a If blood must be given simultaneously with mannitol, add ≥20 mEq of sodium chloride to each liter of mannitol solution.a

Carefully monitor for fluid and electrolyte imbalances.a b

Monitor urine output; serum sodium and potassium concentrations; central venous pressure; degree of hemoconcentration or hemodilution; and renal, cardiac, and pulmonary function.a b

When sorbitol-mannitol irrigation solution is used, consider the cautions, precautions, and contraindications associated with sorbitol.d

Specific Populations

Category C.b d

Not known whether mannitol is distributed into milk.b Caution advised if mannitol is used.b

Safety and efficacy of mannitol injections not established in children <12 years of age.b

Safety and efficacy of sorbitol-mannitol irrigation solution not established.d

Insufficient experience in patients ≥65 years of age in clinical trials;b however, response does not appear to differ from that in younger adults.b Select dosage with caution due to greater frequency of decreased hepatic, renal, and/or cardiac function and of concomitant disease and drug therapy observed in the elderly.b

Substantially eliminated by kidneys; assess renal function periodically since geriatric patients more likely to have decreased renal function.b

Substantially eliminated by kidneys; increased risk of toxic reactions.b

Administer a test dose to patients with severe renal impairment. (See Test Dose under Dosage and Administration.)

Common Adverse Effects

Fluid and electrolyte imbalance.a b

Absorption

Bioavailability

Has been thought not to be absorbed when administered orally; however, about 17% of an oral dose was excreted unchanged in urine.a

Absorbed into systemic circulation following transurethral instillation as sorbitol-mannitol irrigation solution.d

Onset

Following IV administration, diuresis generally occurs within 1–3 hours, lowering of elevated CSF pressure occurs within 15 minutes, and lowering of elevated intraocular pressure occurs within 30–60 minutes.a

Duration

Lowering of elevated CSF pressure and elevated IOP persists for 3–8 and 4–6 hours, respectively, after infusion is stopped.a

Distribution

Extent

Following IV administration, mannitol remains confined to the extracellular compartment; does not cross the blood-brain barrier unless very high concentrations are present in the plasma or the patient has acidosis; and does not penetrate the eye.a

Elimination

Metabolism

Slightly metabolized to glycogen in the liver.a b

Elimination Route

Freely filtered by the glomeruli, with <10% tubular reabsorption; not secreted by tubular cells.a

Excreted principally in urine as unchanged drug.a

Half-life

100 minutes.a

Special Populations

Decreased clearance in patients with renal disease in which glomerular function is impaired.a

Decreased clearance in patients with conditions that impair small vessel circulation (e.g., CHF, cirrhosis with ascitic accumulation, shock, dehydration).a

• Importance of informing clinicians of existing or contemplated concomitant therapy, including prescription and OTC drugs.a

• Importance of women informing clinicians if they are or plan to become pregnant or plan to breast-feed.a

• Importance of informing patients of other important precautionary information. (See Cautions.)