Mannitol contraindications

Azacitidine is contraindicated in patients with a known hypersensitivity to azacitidine or mannitol as well as in patients with advanced malignant hepatic tumors. 

The osmotic diuretics are contraindicated in patients with known hypersensitivity to the drags, electrolyte imbalances, severe dehydration, or anuria and those who experience progressive renal damage after instituting therapy (mannitol). Mannitol is contraindicated in patients with active intracranial bleeding (except during craniotomy). 

The use of urea (Ureaphil, Ur evert) has declined in recent years owing both to its disagreeable taste and to the increasing use of mannitol for the same purposes. When used to reduce cerebrospinal fluid pressure, urea is generally given by intravenous drip. Because of its potential to expand the extracellular fluid volume, urea is contraindicated in patients with severe impairment of renal, hepatic, or cardiac function or active intracranial bleeding. 

Glucose (metabolized), mannitol, urea, glycerin (non-metabolized) and iodine radiocontrast media (incidental) produce an overexpansion of the extracellular fluid and circulatory overload (and are therefore contraindicated in congestive cardiac failure). This is often accompanied by dilutional hyponatraemia, and hyperkalaemia is also possible. Elimination is renal (80-90%). 

Urea is also an intravenous preparation (1 to 1.5 g/kg 0.45 to 0.68 g/lb [30% solution] by slow infusion not to exceed 4 ml/min or 120 g/d). It has a lower molecular weight than mannitol and less of a diuretic effect. Urea is contraindicated in the presence of an intracranial hemorrhage. Urea may increase risk of venous thrombosis and hemoglobinuria in patients who are hypothermic. 

Mannitol, a polyhydiic alcohol (mol. wt. 452), is most commonly used it is given i.v. In addition to its effect on the kidney, mannitol encourages the movement of water from inside cells to the extracellular fluid, which is thus transiently expanded before diuresis occurs. These properties define its uses, which are for rapid reduction of intracraninal or intraocular pressure, and to maintain urine flow to prevent renal tubular necrosis. Because it increases circulatory volume, mannitol is contraindicated in congestive cardiac failure and pulmonary oedema. 

Mannitol Stimulation of osmotic diuresis is possible using mannitol (10-20% solution). (128) Mannitol is neither metabolized in the body nor reabsorbed by the tubules and is excreted almost totally through the kidney. Renal circulation and renal filtration are raised, and by reducing tubular absorption (= osmotic diuresis), water excretion is increased ( diuresis starter ). The saluretic effect is, however, relatively small. In the case of restricted renal function, application of mannitol is contraindicated. If necessary, the mannitol test (i.v. injection of 75 ml of a 20% solution) can be carried out beforehand. With enhanced diuresis of > 40 ml/hr, the kidneys still function adequately, so that it is possible to stimulate osmotic diuresis by means of a mannitol infusion. 

Explain the contraindication of the use of mannitol with heart failure. 

Mannitol, an osmotic diuretic, would not be contraindicated in a client who has glaucoma. The osmotic diuretic medication Diamox is administered to clients with glaucoma. 

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