Influence of Dexamethasone Administration on Hematology, Biochemistry, and Thyroid Hormones in Dogs

Veterinary drug formulary includes many anti-inflammatory drugs, among them Glucocorticoids (GCs). This study evaluated the influence of dexamethasone parenterally (IM) on hematology, biochemistry, thyroid function in normal healthy dogs. Ten mongrel dogs were enrolled in this study, each dog received dexamethasone at a dose of 0.1 mg/kg once daily for 7 days then on an alternate day for 14 days. Blood samples were taken at day 0, day 7, and day 21 of the experiment for determination of CBC, ALT, ALP, Cholesterol, Serum total thyroxine (T4), free T4 (fT4), and thyroid-stimulating hormone (TSH). No significant changes in hematology were recorded throughout the experimental period. Elevation of ALT and ALP was recorded on day 7 and continue on day 21. Total T4 decreased significantly at day 7 and day 21. Free T4 showed a non-significant decrease at day 7 and day 21 compared to day 0 values, TSH showed a non-significant decrease at day 7, however, at day 21, TSH values were elevated to the level of day 0. Dexamethasone administration has an impact on the enzymatic activities of the liver. Administration of dexamethasone at a dosage of 0.1 mg /kg once daily for 7 days decreased total T4, while fT4 was unchanged, suggesting that fT4 may be less affected by daily dexamethasone administration. Administration of dexamethasone every other day meddled with TT4 but its effect on FT4 was minimum. Dexamethasone in this administrated dose has a little effect on serum TSH value.