Pharmacotherapeutic group: Corticosteroid for systemic use, glucocorticoid.
ATCvet code: QH02AB06
Pharmacodynamic properties
Prednisolone is a semi-synthetic corticosteroid derived from the natural hydrocortisone (cortisol). However, the effect on the mineral and glucose metabolism is less (about half) than that of cortisol. This minimizes the unfavourable fluid retention and hypertension.
The effect of prednisolone is anti-inflammatory. When an inflammatory reaction is useful (for example to prevent further invasion of micro-organisms) suppression of this defence mechanism is counterproductive. However, when the inflammatory response is excessive and/or harmful (e.g. a response to an autoimmune or allergic process), the defensive inflammatory response worsens the situation and repression by corticosteroids may be of great therapeutic importance.
- By a protein catabolic effect the formation of granulation tissue is inhibited.
- Inhibition of the inflammation is also achieved by the stabilizing effect of prednisolone on the lysosomal membranes.
- Corticosteroids reduce the development of inflammatory exudate and local oedema by stimulating vasoconstriction and by decreasing the capillary permeability.
- Anti-allergic effect and immunosuppression: these effects are partly related to the anti-inflammatory activity and are mainly directed against cellular (T-lymphocytes) immunoreactivity.
Because orally administered corticosteroids develop their therapeutic effect only after several hours, they are less suitable for the treatment of (acute) anaphylactic reactions such as septic shock.
Pharmacokinetic properties
Following oral administration prednisolone is well absorbed from the gastrointestinal tract and distributes in all tissues, in the body fluids and even in the cerebrospinal fluid. Prednisolone is extensively bound to plasma proteins. It is metabolized in the liver and excretion takes place mainly via the kidneys.