Tromethamine

WARNINGS Large doses of Tromethamine Injection may depress ventilation, as a result of increased blood pH and reduced CO 2 concentration. Thus, dosage should be adjusted so that blood pH is not allowed to increase above normal. In situations in which respiratory acidosis may be present concomitantly with metabolic acidosis, the drug may be used with mechanical assistance to ventilation. Care must be exercised to prevent perivascular infiltration since this can cause inflammation, necrosis and sloughing of tissue. Venospasm and intravenous thrombosis, which may occur during infusion, can be minimized by insuring that the injection needle is well within the largest available vein and that solutions are slowly infused. Intravenous catheters are recommended. If perivascular infiltration occurs, institute appropriate countermeasures (See ADVERSE REACTIONS ). Tromethamine injection should be administered slowly and in amounts sufficient only to correct the existing acidosis, and to avoid overdosage and alkalosis. Overdosage in terms of total drug and/or too rapid administration, may cause hypoglycemia of a prolonged duration (several hours). Therefore, frequent blood glucose determinations should be made during and after therapy. Extreme care should be exercised in patients with renal disease or reduced urinary output because of potential hyperkalemia and the possibility of a decreased excretion of tromethamine. In such patients, the drug should be used cautiously with electrocardiographic monitoring and frequent serum potassium determinations. Because clinical experience has been limited generally to short-term use, the drug should not be administered for more than a period of one day except in a life-threatening situation. The intravenous administration of Tromethamine Injection can cause fluid and/or solute overloading resulting in dilution of serum electrolyte concentrations, overhydration, congested states or pulmonary edema. Additives may be incompatible. Consult with pharmacist, if available. When introducing additives, use aseptic technique, mix thoroughly and do not store.

ADVERSE REACTIONS Generally, side effects have been infrequent. Respiratory: Although the incidence of ventilatory depression is low, it is important to keep in mind that such depression may occur. Respiratory depression may be more likely to occur in patients who have chronic hypoventilation or those who have been treated with drugs which depress respiration. In patients with associated respiratory acidosis, tromethamine should be administered with mechanical assistance to ventilation. Vascular: Extreme care should be taken to avoid perivascular infiltration. Local tissue damage and subsequent sloughing may occur if extravasation occurs. Chemical phlebitis and venospasm also have been reported. Hematologic: Transient depression of blood glucose may occur. Hepatic: Infusion via low-lying umbilical venous catheters has been associated with hepatocellular necrosis. Reactions which may occur because of the solution or the technique of administration include febrile response, infection at the site of injection, venous thrombosis or phlebitis extending from the site of injection extravasation and hypervolemia. If an adverse reaction does occur, discontinue the infusion, evaluate the patient, institute appropriate therapeutic countermeasures and save the remainder of the fluid for examination if deemed necessary.