Therapeutics of Corticosteroids in the Bovine Animal and Problems Surrounding Their Use
Abstract
The corticosteroids have been used extensively in veterinary practice for the last 15 to 20 years. They have offered the practitioners of veterinary medicine a tool useful for blocking a portion of the pathological changes seen in infectious and metabolic disease. Un-fortunately they have done little to advance the cause of specific disease therapy. I shall discuss the use of corticosteroids by veterinarians in some conditions in which they are widely employed and attempt to clarify their usefulness in some cases and their abuse in others.
First let us consider what the pharmacological properties of these agents are and which ones are most likely to be of therapeutic value (Figure 1). The ability of these agents to reduce an elevated temperature, to reduce inflammatory and allergic reactions, to stimulate the central nervous system, to increase the blood glucose levels and to improve the animal's demeanour have broad appeal to the practitioner.
Veterinarians frequently question the dosage of corticosteroids employed in a particular treatment regime and wonder how the suggested dosage would change if he were to employ his "favourite" steroid for the same purpose. Most pharmacology texts have one or more tables relating the potency of these drugs for a variety of parameters (Figure 2).
The glucocorticoid and anti-inflammatory effect of the corticosteroid should be compared and the dosage of the drug to be used determined from the appropriate chart (i.e. if the drug is to be used in ketosis therapy consult the glucocorticoid potency). Of almost equal importance is the sodium retaining property of the drug. In almost all instances the practitioner should select one that does not cause sodium retention in order to avoid the problems of edema formation and fluid build-up that can be harmful to the animal.