Why to Avoid Steroids in Veterinary Practice
Uses of steroids, depict their importance but there is need to keep their side effects in mind while prescribing steroids. Veterinary Assistants of the field, are using steroids blindly in their practice but a good veterinary practitioner prescribes steroids only when they are needed.
Corticosteroids are hormones that are produced either naturally in the cortex of adrenal gland or they are synthetically prepared. There are 3 classes of corticosteroids; glucocorticoid, mineralocorticoid and Androgens or sex steroids . Glucocorticoid is a predominant steroid used in veterinary medicine. Corticosteroids, mentioned in the treatment of animal disorders, are always of the glucocorticoid type. Naturally occurring cortisol is not used, but is replaced by others that can be produced more economically. Their use is generally intended to reduce inflammation and irritation directly or indirectly or to decrease the body’s natural response against itself or outside stimuli. They lessen swelling, redness, itching, and allergic reactions. They are often used as part of the treatment for a number of different diseases, such as severe allergies or skin problems, asthma, or arthritis.
Uses of steroids, mentioned above, depict their importance but there is need to keep their side effects in mind while prescribing steroids. Veterinary Assistants of the field, are using steroids blindly in their practice but a good veterinary practitioner prescribes steroids only when they are needed. There is need to create awareness about steroids to use appropriately. These are side effect of steroids, which all show that, be wise while using steroids:
Increased water consumption and increased urination are two of the most common side effects of glucocorticoid usage. Although it can be quite disconcerting to the owner of a pet that lives predominately in the home, it is not by itself a serious problem. Glucocorticoids increase the activity of the glomeruli, which are the filtration units of the kidneys. This causes the animal to excrete higher levels of urine. The loss stimulates thirst in an attempt to replace lost fluids. These actions may increase water consumption and urination to the point that the animal can control neither one. Such signs can be observed within hours of initiating steroid therapy if the initial dosages were too high for the individual animal to tolerate. When long-acting injectable forms are used at excessive levels, increased water consumption and urination can continue for several weeks.
Changes in attitude and appetite: Some animals will seem more lethargic or tired while on these medications; others may show increased appetites.
Abortion: If given to an animal during pregnancy, glucocorticoids can cause an abortion. Animals on glucocorticoids may be temporarily infertile until the therapy is discontinued.
Immune suppression: During use, and for a period thereafter, higher doses of glucocorticoids will suppress the immune system to some degree and therefore make the animal more susceptible to viral, bacterial, or fungal diseases. To overcome this problem, antibiotics or other medications are frequently given concurrently with steroid therapy to protect the animal from opportunistic organisms taking advantage of the suppressed immune system.
Changes in protein metabolism: Glucocorticoids will alter the animal’s metabolism of protein and can easily lead to muscular weakness or atrophy. With consistent and long-term use, the signs of this can become quite apparent. The abdominal muscles may weaken, causing the animal to have a sagging or pendulous abdomen. Additional strength can be lost from the legs, causing the animal to have difficulty rising after lying down, climbing steps, or walking long distances.
Pancreatitis: There may be a relationship between the use of glucocorticoids and the development of pancreatitis, however, it has not been proven. Glucocorticoids are not recommended for the treatment of pancreatitis, except if the animal is in shock.
Stomach and intestinal ulcers: Again, there may be a relationship between the use of glucocorticoids, especially dexamethasone, and the development of ulcers in the stomach or intestinal tract. This is especially true if the steroids are given to animals also receiving nonsteroidal anti-inflammatory drugs (NSAIDS) such as carprofen (Rimadyl, Novox), deracoxib (Deramaxx), meloxicam (Metacam), and others.
Changes in liver function: Animals treated with glucocorticoids often have increased liver enzymes. If given excessive glucocorticoids, hepatopathy (a liver disease) may occur.
Cushing’s or Cushing-like disease: Many animals treated with high, continuous levels of glucocorticoids can develop symptoms similar to those in Cushing’s disease: increased thirst and urination, panting, and increased appetite. True Cushing’s disease which is an abnormal response of the adrenal gland to stimulation generally does not occur unless the animal has high and long-term exposure to glucocorticoids.
Diabetes and changes in glucose metabolism: Steroids will also alter glucose metabolism, and their use in a diabetic animal can be disastrous. As excessive glucose is produced, the blood sugar elevates abnormally and the animal’s need for insulin increases dramatically.
Changes in calcium utilization: The glucocorticoids also affect calcium utilization in the body. Not only do they cause less calcium to be absorbed through the intestinal wall, but they also cause the kidneys to excrete excessive calcium through the urine. Combined, they cause the body to steal from its own major storage site of calcium, the bones. As it selectively removes calcium from the bones for use in other areas, the bones become weaker and could be more prone to fracture.
Shutdown of the adrenal glands: After steroid therapy is discontinued, or during prolonged use, steroids can have severe effects on the adrenal glands. The brain and the pituitary gland routinely monitor the levels of the mineralocorticoids and glucocorticoids within the body. When their concentrations are low, they signal the adrenal glands to produce more, or vice versa. This system can be fooled by long term administration of glucocorticoids, confusing the synthetic products with those naturally produced by its own adrenal glands. In the presence of higher than normal levels of these compounds, it senses no need for further production and may turn off the adrenal glands completely. Unfortunately, when the medications are later discontinued, the glands are unable to immediately re-initiate normal levels of production. This leaves the body totally without or with greatly reduced concentrations of its own natural regulating steroids. This condition causes the same symptoms as Addison’s disease, but in almost all cases is reversible with time.
Corticosteroids are very beneficial drugs for veterinarian and animals if used wisely. If proper dose of steroids is administered and long term usage is prevented then many of the side effects are overtaken. By keeping proper dose and preventing long term usage we can take excellent results from steroids for treatment of different conditions without any side effect. We must monitor the dosage and response of the animal, many of these effects of glucocorticoid usage are usually easily prevented and the desired beneficial results obtained. Most of these problems, with the exception of induced abortion, are easy to recognize and quickly reversed when steroid usage is decreased or discontinued. When serious problems do occur, it is usually in cases in which steroids were administered over very long periods of time or at excessive doses. Large single doses or short-term use at normal levels rarely, if ever, causes a serious problem unless there is some pre-existing condition such as diabetes, pregnancy, or heart disease.
Babar Rashid1, Sami Ullah Khan Bahadur2, Dr. Razia Kausar3
DVM 9th semester1, M.Phil. Pathology 1st semester2, Deptt. Of Anatomy3, University of Agriculture Faisalabad