Anti-inflammatory and corticosteroid drugs (Copeland) Flashcards
(103 cards)
How are glucocortiosteroids synthesized?
Glucocorticoids are steroid hormones synthesized by the adrenal cortex that are important in regulating many physiological and developmental processes.
Because of anti-inflammatory and immunosuppressant effects, they are widely used to treat a variety of disorders.
Uses of cortiosteroids
to reduce inflammation (asthma, arthritis) and swelling (cerebral edema)
to suppress the immune response (systemic lupus erythematosus, Covid 19)
to reduce nausea and vomiting (as in cancer chemotherapy)
to reduce terminal pain (associated with cancer) as replacement therapy (in Addisons disease)
examples of corticosteroids
•hydrocortisone •prednisolone•dexamethasone•beclomethasone •budesonide•fluticasone
explanation…… to be determined. listen to lecture
Mechanism of the inflammatory response
a. Normal inflammatory response
- series of events that aid our survival in response to injury
b. Mediated by a host of endogenous compounds
-histamine
-serotonin
-complement
-bradykinin
-prostaglandins
-leukotrienes
Properties of Prostaglandins (know picture)
Physiological functions of prostaglandins Pain
PGI2 and PGE2 sensitize nerve endings to bradykinin, histamine and substance P
Physiological Functions of Prostaglandins: Inflammation
Inflammation: PGI2, PGD2 and PGE2 are vasodilators (edema, erythema)
Protection of the gastric mucosa
: PGI2
Maintenance of renal blood flow:
PGE2
Fever:
PGE2
Platelets:
PGI2 and PGD2 inhibit platelet aggregation
TXA2 stimulates platelet aggregation
Uterus and other:
PGD2 contracts uterus
Other: PGE2 keeps ductus arteriosus open following birth
Mechanism of action of NSAIDS
vThe principal therapeutic effects of NSAIDs derive from their ability to inhibit prostaglandin production, the enzymatic activities involved in prostaglandin synthesis.
vThe first enzyme in the prostaglandin synthetic pathway is prostaglandin endoperoxidesynthase, or fatty acid cyclooxygenase. This enzyme converts arachidonic acid to the unstable intermediates PGG2 and PGH2. It is now appreciated that there are two forms of cyclooxygenase, termed cyclooxygenase-1(COX-1) and cyclooxygenase-2 (COX-2).
Mechanism of NSAIDs 2
ØNSAID inhibition of PG production alleviates most of the pathologic effects associated with inflammation, but it also interferes with the physiologic role of these molecules
ØConsequently, long-term therapy with nonspecific NSAIDs is frequently limited by their adverse effects, particularly those caused by erosion of gastric mucosal protection
- GI bleeding
3 Types of Cox
Three types of cyclooxygenase:
- COX-1 is constitutively expressed
- COX-2 is induced at sites of inflammation by inflammatory mediators
- COX-3 recently identified
Know know this: mainly COX
inhibit thromboxanes, prostaglandins and prostcyclin at the same time
Cox 1, 2,3, function
vCOX-1 is expressed in all tissues and serves a variety of homeostatic physiologic functions. COX-1 is responsible for the production of protective prostaglandins in the kidney and stomach, as well as the functional thromboxane of platelets.vCOX-2, Not normally found in most tissues, expressed under conditions of tissue damage and plays an active role in the inflammatory response.vCOX-3, found primarily in cerebral cortex and heart
cox hypothesis
clinical indication of NSAIDs
Prevent or interrupt mild to moderate pain associated with inflammatory conditions without altering consciousness (analgesic, anti-inflammatory)
Pain quality is often described as a dull ache in
• joint pain (osteoarthritis, gout)• muscle pain (myalgia)• headache (non migraine)
Reduce elevated body temperature (fever) (antipyretic)
Pain
NSAIDs usually are classified as mild analgesics
A consideration of the type of pain as well as its intensity is important in the assessment of analgesic efficacy.
They are particularly effective in settings in which inflammation has caused sensitization of pain receptors to normally painless mechanical or chemical stimuli. Pain that accompanies inflammation and tissue injury probably results from local stimulation of pain fibers and enhanced pain sensitivity (hyperalgesia), in part a consequence of increased excitability of central neurons in the spinal cord
In general, NSAIDs do not effect the hyperalgesia or the pain caused by direct action of prostaglandins, consistent with the concept that the analgesic effects of these agents are due to inhibition of prostaglandin synthesis.
Inflammation
Inflammatory responses occur in three distinct phases, each apparently mediated by different mechanisms:
an acute transient phase, characterized by local vasodilatation and increased capillary permeability;
a delayed, subacute phase, most prominently characterized by infiltration of leukocytes and phagocytic cells; and
a chronic proliferative phase, in which tissue degeneration and fibrosis occur.
Fever
Regulation of body temperature requires a delicate balance between the production and loss of heat; the hypothalamus regulates the set point at which body temperature is maintained
The cytokines increase the synthesis of PGE2 in the hypothalamic area; and PGE2 increases in cyclic AMP triggers the hypothalamus to elevate body temperature by promoting increases in heat generation and decreases in heat loss.
NSAIDs suppress this response by inhibiting the synthesis of PGE2
Shared Therapeutic Activities and Side Effects of NSAIDs
All NSAIDs are analgesic, antiinflammatory, and antipyretic
these drugs usually are effective only against pain of low-to-moderate intensity
NSAIDs do not change the perception of sensory modalities other than pain.
As antipyretics, NSAIDs reduce the body temperature