Question

Would an medication that contains 50 mg of Frusemide (4-chloro-N-furfuryl-5-sulphamoylanthranilic acid) increases the TCO2 in horses?

Answer 1

FRUSEMIDE:

1. It is most commonly used in horses to prevent bleeding during a race or to reduce the incidence of EXERCISE-INDUCED PULMONARY HEMORRHAGE because of its diuretic effects
2. It also used for Pulmonary Edema,Congestive Heart Failure and allergic reactions in horses although it increases circulation to kidneys it does not help kidney function so it is not recommended for kidney disease.

DOSE: 0.5 - 1.0mg/kg twice/day either intramuscularly or intravenously

SIDE EFFECTS:

1. Dehydration
2. Loss of Potassium, Calcium, Sodium, Magnesium
3. Excessive Use - Metabolic Alkalosis (increases in bicarbonate ions) due to hypochloremia and hypokalemia

TCO₂ (TOTAL CARBONDIOXIDE) TEST: It is the test used to indicate the amount of carbondioxide  in the arterial,venous or capillary whole blood

• Its clinical significance is to measure carbondioxide in all forms including in physical solution or loosely bound to proteins, Bicarbonates or Carbonate anions and Carbonic Acid but chiefly to evaluate the bicarbonate concentration.

THRESHOLD VALUES FOR TCO2 (In Horses)	WITH FRUSEMIDE	WITHOUT FRUSEMIDE	FOR BOTH (PROPOSED)
Values	39mmoles TCO2/ml Plasma	37 mmoles TCO2/ml Plasma	37 mmoles TCO2/ml Plasma

• The increase in TCO₂ in horses of 50 mg depends on the DOSE as the dose is given on the basis of weight of the horse and the TIME INTERVAL between injection and blood sampling(Sampling within 3 Hrs of injection can't give accurate range)
• As per the above question, 50 mg of Frusemide may or maynot increase th TCO₂ level as the weight and the sampling time is not given and it definitely increase in case of overuse.