Mannitol Lavoisier (Mannitol)

Mannitol is used in clinical situations that require rapid osmotic diuresis or reduction of fluid pressure.

• Intracranial hypertension: lowers intracranial pressure by drawing fluid from brain tissue into the vascular compartment.
• Acute renal failure: promotes urine output to assist renal clearance when kidney function is compromised.
• Ocular hypertension: reduces intraocular pressure during surgical procedures or acute attacks.
• Fluid overload in cardiac surgery: facilitates removal of excess extracellular fluid to improve hemodynamic stability.
• Hyperosmolar emergencies: provides rapid plasma osmolarity increase to manage severe hypernatremia.

• Mannitol acts as an osmotically active agent that raises plasma osmolality when administered intravenously. The increased extracellular osmotic pressure draws water from intracellular and interstitial compartments into the vascular space, expanding intravascular volume and promoting renal filtration. The resulting diuresis helps to lower intracranial and intraocular pressures and to flush renal tubules in acute kidney injury. It does not undergo significant metabolism and is eliminated unchanged by glomerular filtration.

Mannitol may be associated with a range of adverse reactions, varying from mild to severe.

Common Side Effects

• Headache: mild to moderate pain often reported during infusion.
• Nausea or vomiting: gastrointestinal discomfort occurring shortly after administration.
• Electrolyte imbalance: shifts in sodium or potassium levels.
• Thirst or dry mouth: sensation of increased fluid need.
• Transient hypotension: mild drop in blood pressure during rapid infusion.
• Dizziness: light‑headed feeling during or after infusion.

Serious or Rare Side Effects

• Pulmonary edema: accumulation of fluid in lungs, especially in patients with cardiac dysfunction.
• Acute renal failure worsening: paradoxical decrease in urine output.
• Severe electrolyte disturbances: hypernatremia or hyponatremia requiring urgent correction.
• Anaphylactic reaction: rare hypersensitivity with rash, bronchospasm, or circulatory collapse.
• Seizures: rare neurologic event linked to rapid osmotic shifts.

When using Mannitol, clinicians should observe specific precautions to minimise risks and ensure therapeutic effectiveness.

• Assess renal function: confirm adequate glomerular filtration before initiating therapy.
• Monitor fluid balance: track input and output to avoid overload.
• Check electrolytes: regularly measure serum sodium and potassium levels.
• Adjust infusion rate: use controlled infusion to prevent rapid plasma osmolar changes.
• Avoid in severe heart failure: risk of pulmonary edema is heightened.
• Store at 2-8°C: keep refrigerated, protect from light, do not freeze.

Mannitol can interact with several medicines, influencing its efficacy or safety profile.

Major Interactions (Avoid)

• Loop diuretics: may potentiate excessive diuresis and electrolyte loss.
• Lithium: increased risk of lithium toxicity due to altered renal clearance.
• Antihypertensives: additive hypotensive effect when combined with rapid infusion.

Moderate Interactions (Monitor Closely)

• ACE inhibitors or ARBs: monitor blood pressure and renal function.
• Aminoglycoside antibiotics: watch for nephrotoxicity when renal perfusion is reduced.
• Insulin: osmotic shifts may affect glucose control, requiring dose adjustment.