Generic name: mannitol injection [ MAN-it-ol ]
Brand name: Osmitrol
Dosage form: intravenous solution (10%; 15%; 20%; 25%)
Drug class: Miscellaneous diuretics

Medically reviewed by Drugs.com on Aug 16, 2023. Written by Cerner Multum.

What is mannitol?

Mannitol is a diuretic that is used to reduce swelling and pressure inside the eye or around the brain.

Mannitol is also used to help your body produce more urine. mannitol injection is used in people with kidney failure, to remove excess water and toxins from the body.

Mannitol is sometimes given so that your body will produce enough urine to be collected and tested. This helps your doctor determine if your kidneys are working properly.

Mannitol may also be used for purposes not listed in this medication guide.

Mannitol side effects

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Tell your caregivers right away if you have:

• swelling in your hands or lower legs, rapid weight gain;

• little or no urination;

• shortness of breath (even while lying down);

• wheezing, gasping for breath, cough with foamy mucus;

• chest pain, fast heartbeats;

• headache, or feeling like you might pass out;

• a seizure;

• painful or difficult urination;

• pain, bruising, irritation, or skin changes where the injection was given;

• dehydration symptoms--feeling very thirsty or hot, being unable to urinate, heavy sweating, or hot and dry skin; or

• signs of an electrolyte imbalance--increased thirst or urination, confusion, vomiting, constipation, muscle pain or weakness, leg cramps, bone pain, lack of energy, irregular heartbeats, tingly feeling.

Common side effects of mannitol injection may include:

• increased urination;

• nausea, vomiting;

• fever, chills, headache, runny nose;

• chest pain;

• rash; or

• dizziness, blurred vision.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Related/similar drugs

Warnings

You should not receive mannitol if you have severe kidney disease, lung swelling or congestion, severe heart failure, severe dehydration, bleeding in your brain not caused by surgery, or if your kidneys have already shut down and you are unable to urinate.

Before taking this medicine

You should not receive mannitol if you are allergic to it, or if you have:

• severe or long-term kidney disease;

• swelling or congestion in your lungs;

• severe heart failure;

• bleeding in your brain that is not related to surgery;

• severe dehydration; or

• if your kidneys have already shut down and you are unable to urinate.

Tell your doctor if you have ever had:

• kidney disease;

• heart disease; or

• an electrolyte imbalance (such as low levels of potassium or sodium in your blood).

Tell your doctor if you are pregnant or breastfeeding.

How is mannitol given?

Mannitol is given as an infusion into a vein. A healthcare provider will give you this injection.

Mannitol must be given slowly, and you may receive the medication around the clock.

Tell your caregivers if you feel any burning, pain, or swelling around the IV needle when mannitol is injected.

You will need frequent medical tests to be sure mannitol injection is not causing harmful effects. This will also help your doctor determine how long to treat you with mannitol.

This medicine may affect certain medical tests and you may have false results. Tell any doctor who treats you that you are using mannitol.

Mannitol injection dosing information

Usual Adult Dose for Oliguria:

Renal function test dose prior to initiation of treatment: 0.2 g/kg IV over 3 to 5 min resulting in a urine flow of at least 30 to 50 mL/hr. A second test dose may be administered if the urine flow does not increase. If no response is seen following the second test dose, the patient should be reevaluated.

Treatment: 300 to 400 mg/kg (21 to 28 g for a 70 kg patient) or up to 100 g of 15% to 20% solution IV once. Treatment should not be repeated in patients with persistent oliguria.

Prevention (for use during cardiovascular and other types of surgery): 50 to 100 g IV. usually a 5 , 10, or 20% solution is used depending on the fluid requirements of the patient.

Usual Adult Dose for Cerebral Edema:

0.25 to 2 g/kg as a 15 to 20% solution IV over at least 30 min administered not more frequently than every 6 to 8 hrs.

To yield a satisfactory reduction in intracranial pressure, the osmotic gradient between the blood and cerebrospinal fluid should remain approximately 20 mOsmol.

In small &/or debilitated patients 500 mg/kg may be sufficient.

What happens if I miss a dose?

Because you will receive mannitol in a clinical setting, you are not likely to miss a dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Overdose symptoms may include confusion, severe weakness, vomiting, loss of coordination, sweating, chest pain, severe shortness of breath, and fainting.

What should I avoid after receiving mannitol?

Follow your doctor's instructions about any restrictions on food, beverages, or activity.

What other drugs will affect mannitol?

Mannitol can harm your kidneys, especially if you also use certain medicines for infections, cancer, osteoporosis, organ transplant rejection, bowel disorders, high blood pressure, or pain or arthritis (including Advil, Motrin, and Aleve).

Tell your doctor about all your other medicines, especially a diuretic or "water pill."

Other drugs may affect mannitol, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell your doctor about all your current medicines and any medicine you start or stop using.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Medical Disclaimer

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