Ionosol

Ionosol MB and 5% Dextrose Injection contains a hypotonic concentration of electrolytes with dextrose. The letters “MB” mean “modified Butler’s” solution; the modified solution contains 5 mEq less sodium, 5 mEq more potassium, and 3 mEq added magnesium, as compared with the original Butler’s solution. The modified solution can be used in pediatric patients for treatment of dehydration, acidosis, diarrhea, or burns, and in adults for postoperative fluid and electrolyte therapy.

Solutions containing dextrose restore blood glucose levels and provide calories. Carbohydrate in the form of dextrose may aid in minimizing liver glycogen depletion and exerts a protein-sparing action. Dextrose injected parenterally undergoes oxidation to carbon dioxide and water.

The lactate anion provides an alkalizing effect resulting from simultaneous removal by the liver of lactate and hydrogen ions. In the liver, the lactate is metabolized to glycogen which is ultimately converted to carbon dioxide and water by oxidative metabolism.

The lactate anion acts as a source (alternate) of bicarbonate when normal production and utilization of lactic acid is not impaired as a result of disordered lactate metabolism. Since metabolic conversion is dependent on the integrity of cellular oxidative processes, lactate may be inadequate or ineffective as a source of bicarbonate in patients suffering from acidosis associated with shock or other disorders involving reduced perfusion of body tissues. When oxidative activity is intact, one to two hours time is required for metabolism of lactate.

Magnesium chloride in water dissociates to provide magnesium (Mg++) and chloride (Cl‾) ions. Magnesium is the second most plentiful cation of the intracellular fluids. It is an important cofactor for enzymatic reactions and plays an important role in neurochemical transmission and muscular excitability. Normal plasma concentration ranges from 1.5 to 2.5 or 3.0 mEq/liter. Magnesium is excreted solely by the kidney at a rate proportional to the plasma concentration and glomerular filtration.

Phosphate is one of the three major intracellular electrolytes (along with potassium and magnesium) and the largest anion component found within the cells. Its concentration and excretion are largely dependent on intake, acid-base balance and endocrine function. Its metabolism follows that of calcium in many respects. Phosphate anion in electrolyte solutions may help to repair phosphate deficiency.

Potassium chloride in water dissociates to provide potassium (K+) and chloride (Cl‾) ions. Potassium is the chief cation of body cells (160 mEq/liter of intracellular water). It is found in low concentration in plasma and extracellular fluids (3.5 to 5.0 mEq/liter in a healthy adult and child over 10 days old; 3.5 to 6.0 mEq/liter in a child less than 10 days old). Potassium plays an important role in electrolyte balance. Normally about 80 to 90% of the potassium intake is excreted in the urine; the remainder in the stools and to a small extent, in the perspiration. The kidney does not conserve potassium well so that during fasting or in patients on a potassium-free diet, potassium loss from the body continues resulting in potassium depletion.

Water is an essential constituent of all body tissues and accounts for approximately 70% of total body weight. Average normal adult daily requirement ranges from two to three liters (1.0 to 1.5 liters each for insensible water loss by perspiration and urine production). Average normal pediatric daily requirements are based on the child’s weight as described in the table below:

Water balance is maintained by various regulatory mechanisms. Water distribution depends primarily on the concentration of electrolytes in the body compartments, and sodium (Na+) plays a major role in maintaining physiologic equilibrium.

Ionosol MB and 5% Dextrose Injection contains a hypotonic electrolyte concentration. This should not be confused with the total tonicity (electrolytes plus nonelectrolytes) of solutions containing both electrolytes and dextrose. In general, solutions providing isotonic electrolyte concentrations are most applicable to replacement of acute deficits, whereas hypotonic electrolyte concentrations are best suited for parenteral maintenance of water requirements when only small quantities of electrolytes are desired.

Ionosol MB and 5% Dextrose Injection is indicated for intravenous administration to infants for treatment of dehydration, acidosis, diarrhea, and burns, but only after administration of an initial priming solution: 15 mL of 5% dextrose and 0.45% Sodium Chloride Injection/kg of body weight.

In adults, Ionosol MB and 5% Dextrose Injection is indicated postoperatively for intravenous fluid and electrolyte maintenance therapy, with a small amount of carbohydrate calories for reducing catabolism of endogenous protein reserves.

Solutions which contain potassium ions should be used with great care, if at all, in patients with hyperkalemia, severe renal failure and in conditions in which potassium retention is present.

Solutions containing sodium ions should be used with great care, if at all, in patients with congestive heart failure, severe renal insufficiency and in clinical states in which there exists edema with sodium retention.

In patients with diminished renal function, administration of solutions containing sodium or potassium ions may result in sodium or potassium retention.

Solutions containing lactate ions should be used with great care, if at all, in patients with metabolic or respiratory alkalosis. The administration of lactate ions should be done with great care in those conditions in which there is an increased level or an impaired utilization of lactate ions, such as severe hepatic insufficiency.

The intravenous administration of Ionosol MB and 5% Dextrose Injection can cause fluid and/or solute overloading resulting in dilution of serum electrolyte concentrations, overhydration, congested states or pulmonary edema.

The risk of dilutional states is inversely proportional to the electrolyte concentrations of administered parenteral solutions. The risk of solute overload causing congested states with peripheral and pulmonary edema is directly proportional to the electrolyte concentrations of such solutions.

Clinical evaluation and periodic laboratory determinations are necessary to monitor changes in fluid balance, electrolyte concentrations and acid-base balance during prolonged parenteral therapy or whenever the condition of the patient warrants such evaluation.

Caution must be exercised in the administration of parenteral fluids, especially those containing sodium ions, to patients receiving corticosteroids or corticotropin.

Solutions containing lactate ions should be used with caution as excess administration may result in metabolic alkalosis.

Solutions containing dextrose should be used with caution in patients with known subclinical or overt diabetes mellitus.

Do not administer unless solution is clear and container is undamaged. Discard unused portion.

Pregnancy Category C. Animal reproduction studies have not been conducted with Ionosol solutions. It is also not known whether Ionosol solutions can cause fetal harm when administered to a pregnant woman or can affect reproduction capacity. Ionosol solutions should be given to a pregnant woman only if clearly needed.

Geriatric Use: An evaluation of current literature revealed no clinical experience identifying differences in response between elderly and younger patients. In general, dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy.

This drug is known to be substantially excreted by the kidney, and the risk of toxic reactions may be greater in patients with impaired renal function. Because elderly patients are more likely to have decreased renal function, care should be taken in dose selection, and it may be useful to monitor renal function.

Pediatric Use: The safety and effectiveness in the pediatric population are based on the similarity of the clinical conditions of the pediatric and adult populations. In neonates or very small infants the volume of fluid may affect fluid and electrolyte balance.

Frequent monitoring of serum glucose concentrations is required when dextrose is prescribed to pediatric patients, particularly neonates and low birth weight infants.

In very low birth weight infants, excessive or rapid administration of dextrose injection may result in increased serum osmolality and possible intracerebral hemorrhage.

In the event of overhydration or solute overload during therapy, re-evaluate the patient and institute appropriate corrective measures. See WARNINGS and PRECAUTIONS.