Uses of Mannitol 20

☰ Table of content

1. What is Mannitol?

Mannitol 20% is formulated as an intravenous infusion solution available in volumes of 250 ml and 500 ml. Mannitol 20% is a product of Mekophar Chemical and Pharmaceutical Joint Stock Company.

Mannitol is an osmotic diuretic with minimal energy value as it is rapidly excreted from the body unchanged along with a corresponding volume of urine before undergoing metabolism. The half-life of Mannitol 20 is approximately 100 minutes (in individuals with normal renal function). In patients with renal insufficiency, Mannitol 20 accumulates in the body, promoting the movement of water into the vascular space, resulting in intracellular dehydration and hyponatremia.

Mannitol is isomeric with sorbitol. Upon intravenous administration, Mannitol 20 is quickly distributed into the interstitial space. Consequently, the drug's action increases the osmolarity of plasma and tubular fluid in the kidneys, causing osmotic diuresis and increasing renal blood flow. The efficacy of Mannitol 20 is greater than that of dextrose (due to its limited metabolism and reabsorption in the renal tubules). Mannitol 20 is primarily employed for osmotic diuresis to protect renal function during acute renal failure, to reduce intracranial pressure, and to manage intraocular pressure. Furthermore, Mannitol 20 is also used for induced diuresis in cases of overdose.

Mannitol 20 should not be administered to patients with heart failure, as it causes a sudden increase in blood volume. High doses of Mannitol 20 in the treatment of cerebral edema may alter the volume, osmolarity, and composition of the extracellular fluid to levels that could lead to acute renal failure, decompensated heart failure, and various other complications. Intravenous Mannitol 20 is also utilized during cardiac surgery, various other surgical procedures, or following trauma.

2. Indications for Mannitol 20

Mannitol 20 is indicated in the following situations:

• Prevention of acute tubular necrosis due to hypotension;
• Treatment of oliguria post-surgery;
• Supportive treatment of poisoning due to its ability to induce diuresis for increased excretion of toxic substances via urine;
• Reduction of intracranial pressure in the management of cerebral edema;
• Supportive treatment to lower intraocular pressure;
• Utilization before and during ocular surgeries;
• Mannitol 20 is also indicated for renal function testing or irrigation during transurethral prostatectomy.

3. Dosage of Mannitol

Dosage for renal function testing: Administer intravenously 200 mg/kg body weight or 12.5 g of 15% or 25% Mannitol solution over a duration of 3 to 5 minutes. This dosage will stimulate urine output of 30-50 ml per hour for 2 to 3 hours post-infusion of Mannitol. If the initial response is ineffective, a second test may be performed with a similar dosage. If urine output after Mannitol testing is below 30-50 ml/hour, renal parenchymal damage is indicated (and Mannitol treatment is contraindicated in such cases).

Prevention of acute renal injury: Administer intravenously 50 to 100 g of Mannitol 5 to 25%. The infusion rate of Mannitol 20 is adjusted to achieve a urine output of at least 30 to 50 ml/hour.

Mannitol dosage for supportive elimination of toxins: Administer similarly to the urgent prevention of acute renal failure, but maintain urine output of at least 100 ml/hour, generally 500 ml/hour, and sustain a positive fluid balance of 1-2 liters.

Mannitol dosage to reduce nephrotoxicity from cisplatin: Rapidly infuse 12.5 g of Mannitol just prior to cisplatin administration, then maintain an infusion of 20% Mannitol at 10 g/hour for 6 hours while ensuring urine output remains above 100 ml/hour.

Concurrently, fluid replacement must be provided with 0.45% sodium chloride and potassium chloride at 20-30 mEq/liter at a rate of 250 ml/hour for 6 hours.

Mannitol dosage for reduction of intracranial pressure: Administer a rapid intravenous infusion of 15% to 25% Mannitol at a dose of 1 to 2 g/kg over 30-60 minutes. An intact blood-brain barrier may allow Mannitol infusion to reduce intracranial pressure.

Mannitol dosage for reduction of intraocular pressure: Administer 1.5-2 g/kg over 30-60 minutes using 15-20% Mannitol solution. The ocular-hypotensive effect manifests within 15 minutes of Mannitol administration and lasts for 3 to 8 hours post-infusion.

Mannitol dosage during transurethral prostatectomy: Use Mannitol 2.5% to 5% for bladder irrigation during the procedure.

Mannitol 20 dosage in pediatrics:

• For the treatment of oliguria or anuria: Perform testing with a 200 mg/kg dose similar to adults; if no renal damage is present, administer 2 g/kg intravenously using 15-20% Mannitol solution over 2 to 6 hours;
• For reduction of intracranial pressure or intraocular pressure: Administer 2 g/kg intravenously over 30-60 minutes using 15-25% solution;
• For management of poisoning: Administer 2 g/kg with a 5-10% solution intravenously to maintain a high urine output;

Mannitol 20 dosage for the elderly: It is advisable to initiate treatment with the lowest dosage and adjust according to individual patient response.

4. Contraindications for Mannitol 20

Mannitol 20 is contraindicated in the following cases:

• Dehydration;
• Congestive heart failure;
• Severe heart disease;
• Intracranial hemorrhage following cranial trauma (except during open craniotomy);
• Edema due to metabolic disorders with capillary rupture;
• Severe renal failure (except in cases responsive to diuretic testing; lack of response or poor response may lead to increased extracellular fluid volume and acute water intoxication);
• Oliguria or anuria following mannitol testing.

5. Drug Interactions of Mannitol 20

• Mannitol 20 should not be infused concurrently with whole blood;
• Patients on lithium therapy should be monitored for drug response when using Mannitol 20.

6. Adverse Effects of Mannitol 20

During the administration of Mannitol 20, patients may experience several adverse effects:

• Common adverse effects of Mannitol 20 include: increased extracellular fluid volume, circulatory overload, thrombophlebitis, chills, fever, headache, nausea, vomiting, thirst, diarrhea, water and electrolyte imbalance, acid-base imbalance, chest pain, blurred vision;
• Rare adverse effects of Mannitol 20 include: extravasation leading to tissue edema and necrosis, tachycardia, osmotic nephrosis, acute renal failure, allergic reactions such as urticaria, anaphylactic shock, dizziness.

Precautions when using Mannitol 20:

• Before administering Mannitol 20, ensure that the patient is not dehydrated;
  During the infusion of Mannitol 20, closely monitor fluid and electrolyte balance, serum osmolality, renal function, and vital signs of the patient;
• If the rate of fluid infusion exceeds the rate of urine output, this may lead to water intoxication;
• The prolonged diuretic effect of Mannitol 20 may obscure signs of inadequate fluid replacement or reduced circulatory volume;
• The intravenous infusion set for Mannitol 20 must be compatible with a built-in filter;
• Mannitol 20 should not be infused concurrently with whole blood;
• Before administering Mannitol 20, check the compatibility of any additives to the mannitol solution;
• Due to its hypertonic nature, Mannitol 20 solution should only be administered intravenously, as extravasation may lead to tissue necrosis;
• Mannitol 20 may increase hydrogen gas levels in the colonic lumen to the extent that it could cause bowel perforation when treated with thermal therapy;
• Mannitol 20 may be used during pregnancy.

7. Storage of Mannitol 20

Store Mannitol 20 at room temperature between 15 - 30 degrees Celsius, avoiding freezing. Crystallization may occur in solutions containing over 15% mannitol, particularly when stored at low temperatures; in such cases, the Mannitol 20 vial may be immersed in warm water to dissolve the crystals.

Mannitol 20 is an osmotic diuretic used for preventing acute renal failure or treating increased intracranial pressure or intraocular pressure. To ensure therapeutic efficacy and to avoid undesirable side effects, patients must use the medication as directed by qualified healthcare professionals. 

For further health information, nutrition, and beauty tips to protect your health and that of your loved ones, please refer to the International General Hospital Vinmec website.

To arrange an appointment, please call HOTLINE or make your reservation directly HERE. You may also download the MyVinmec app to schedule appointments faster and manage your reservations more conveniently.