mannitol

mannitol /man·ni·tol/ (man´i-tol) a sugar alcohol formed by reduction of mannose or fructose and widely distributed in plants and fungi; an osmotic diuretic used to prevent and treat acute renal failure, to promote excretion of toxic substances, to reduce cerebral edema or elevated intracranial or intraocular pressure, and to prevent hemolysis during transurethral surgical procedures.

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man·ni·tol (mn-tôl, -tl)

n.

A white, crystalline, water-soluble, slightly sweet alcohol, used as a dietary supplement and dietetic sweetener and in medical tests of renal function.

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mannitol

(man´itol´),
n a poorly metabolized sugar used as an osmotic diuretic and in kidney function tests.

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mannitol

a sugar alcohol occurring widely in nature, especially in fungi; utilization of mannitol is used in identification of some bacteria; used in diagnostic tests of kidney function and as an osmotic diuretic, particularly in the treatment of cerebral edema and oliguric acute renal failure.

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mannitol

Osmitrol, Resectisol

Pharmacologic class: Osmotic diuretic

Therapeutic class: Diuretic

Pregnancy risk category C

Action

Increases osmotic pressure of plasma in glomerular filtrate, inhibiting tubular reabsorption of water and electrolytes (including sodium and potassium). These actions enhance water flow from various tissues and ultimately decrease intracranial and intraocular pressures; serum sodium level rises while potassium and blood urea levels fall. Also protects kidneys by preventing toxins from forming and blocking tubules.

Availability

Injection: 5%, 10%, 15%, 20%, 25%

Solution: 5 g/100 ml

⊘Indications and dosages

➣ Test dose for marked oliguria or suspected inadequate renal function

Adults: 0.2 g/kg I.V. infusion (approximately 50 ml of 25% solution, 75 ml of 20% solution, or 100 ml of 15% solution) over 3 to 5 minutes. If urine flow doesn't increase, second dose may be given; if response is inadequate after second dose, reevaluate patient.

➣ To prevent acute renal failure during cardiovascular and other surgeries

Adults: 50 to 100 g I.V. infusion as 5% to 25% solution, up to 6 g/kg/day

➣ Acute renal failure

Adults: 50 to 100 g I.V. infusion as 15% to 25% solution, up to 6 g/kg/day

➣ To reduce intracranial pressure and brain mass

Adults: 0.5 to 2 g/kg I.V. infusion as 15% to 25% solution given over 30 to 60 minutes

➣ To reduce intraocular pressure

Adults: 0.5 to 2 g/kg I.V. infusion as 15% to 25% solution given over 30 to 60 minutes. For preoperative use, give 60 to 90 minutes before surgery.

➣ To promote diuresis in drug toxicity

Adults: 25 g I.V. infusion as loading dose, followed by infusion of 5% to 25% solution given continuously to maintain high urine output

➣ Irrigation during transurethral resection of prostate

Adults: 2.5% to 5% solution instilled into bladder via indwelling urethral catheter, as needed

Contraindications

• Active intracranial bleeding (except during craniotomy)
• Anuria secondary to severe renal disease
• Progressive heart failure, pulmonary congestion, renal damage, or renal dysfunction after mannitol therapy begins
• Severe pulmonary congestion or pulmonary edema
• Severe dehydration

Precautions

Use cautiously in:
• severe renal disease, heart failure, mild to moderate dehydration
• pregnant or breastfeeding patients.

Administration

☞ Withhold drug until adequate renal function and urinary output are established.
• Be aware that at low temperatures, solution may crystallize (especially concentrations above 15%). If crystals form, warm bottle in hot-water bath or dry-heat oven or autoclave, then cool to body temperature or lower before giving.
• Don't give electrolyte-free mannitol solutions with blood; when giving blood with mannitol, add 20 mEq or more of sodium chloride solution to each liter of mannitol solution to avoid pseudoagglutination.
• Know that drug may be given as continuous or intermittent I.V. infusion. Infuse at prescribed rate using infusion device and in-line filter. Give single I.V. dose over 30 to 90 minutes in adults.
☞ Avoid extravasation, because it may cause local edema and tissue necrosis.

Route	Onset	Peak	Duration
I.V. (diuresis)	1-3 hr	Unknown	Up to 8 hr
I.V. (intraocular press.)	30-60 min	Unknown	4-8 hr
I.V. (intracranial press.)	15 min	Unknown	3-8 hr

Adverse reactions

CNS: dizziness, headache, seizures

CV: chest pain, hypotension, hypertension, tachycardia, thrombophlebitis, heart failure, vascular overload

EENT: blurred vision, rhinitis

GI: nausea, vomiting, diarrhea, dry mouth

GU: polyuria, urinary retention, osmotic nephrosis

Metabolic: dehydration, water intoxication, hypernatremia, hyponatremia, hypovolemia, hypokalemia, hyperkalemia, metabolic acidosis

Respiratory: pulmonary congestion

Skin: rash, urticaria

Other: chills, fever, thirst, edema, extravasation with edema and tissue necrosis

Interactions

Drug-drug. Digoxin: increased risk of digoxin toxicity

Diuretics: increased therapeutic effects of mannitol

Lithium: increased urinary excretion of lithium

Drug-diagnostic tests. Electrolytes: increased or decreased levels

Patient monitoring

☞ Monitor I.V. site carefully to avoid extravasation and tissue necrosis.
• In comatose patient, insert indwelling urinary catheter as ordered to monitor urine output.
• Monitor renal function tests, urinary output, fluid balance, central venous pressure, and electrolyte levels (especially sodium and potassium).
☞ Watch for excessive fluid loss and signs and symptoms of hypovolemia and dehydration.
☞ Assess for evidence of circulatory overload, including pulmonary edema, water intoxication, and heart failure.

Patient teaching

• Teach patient about importance of monitoring exact urinary output.
☞ Advise patient to report pain at infusion site as well as adverse reactions, such as increased shortness of breath or pain in back, legs, or chest.
• Tell patient drug may cause thirst or dry mouth. Emphasize that fluid restrictions are necessary, but that frequent mouth care should ease these symptoms.
• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs and tests mentioned above.