Dexamethasone pharmacology | Dexamethasone moa uses side effects | pharmacology of dexamethasone
Hello assalamu alaikum to all today we are going to study the pharmacology of a drug called the hexamethasone which is going to be very helpful in treating copin 19 it is the first and only drug that significantly improves survival in kovid19 patients so let’s start dexamethasone is a synthetic corticosteroid now firstly what is mean by corticosteroids
Corticosteroids are actually the hormones that are naturally released in our body on the top of each kidney we have a glands on them then client is known as adrenal gland add renal add means on and renal means kidney so it is the gland at present on the kidney on the top of each kidney and that adrenal gland has two main parts the outer part is known as availa
Cortex while the inner part is known as adrenal medulla adrenal cortex is take part that releases corticosteroids and these corticosteroids have a number of functions in our body they are involved in the metabolism of carbohydrate proteins fat and clinically they may be used as an anti-inflammatory and immunosuppressive agent so dexamethasone is a synthetic
Corticosteroids and those corticosteroids that that are naturally released in our body that are endogenous they include glucocorticoids and mineralocorticoids that also are various types it is approved by fda 1958 as it is synthetic one so obviously it is much more strong and potent than androgenous corticosteroids potent indicating potency potency means the
Ability of a drug to binding to its receptor and dexamethasone is highly potent than androgenous corticosteroids they binds 20 to 30 times more strongly than the endogenous corticosteroid to its corticoid receptors now how dexamethasone works in clinical scenario it works as an anti-inflammatory and immunosuppressive agent now how it can beat inflammation how
It causes immunosuppression to understand that concept firstly we have to understand the basic mechanism of inflammation means what are the mediators of inflammation what causes inflammation how dexamethasone acts on it and inhibit inflammation so here is the pictorial diagram of inflammatory mechanism as you can see here basically what happens when our cells
Become dead or enjoyed they release some chemicals that include histamine prostaglandin bradykinin and these chemicals send signals they send signals to the vessels around the tissue around that injury tissue number one to become more dilated and second to become more permeable okay to become more dilated and to become more permeable due to increase in dilation
And increase in permeability the fluid in the vessel gets fluid they get leaked out into the tissues there is a fluid deposition out of the vessel that results in swelling of the tissue or you can say edema occur secondly these chemicals also attract over infection-fighting leukocytes our infection-fighting leukocytes that are also called inflammatory cells and
These cells including platelets basophils monocytes macrophages and these cells these inflammatory cells get can get traveled to the site of injury and when they get entry into the site of injury they are they undergo phagocytosis they undergo phagocytosis and consume over dead tissues or you can say in joy tissues and cell diabetes so this is the basic mechanism
Of inflammation now real dexamethasone and view it exon the anti-inflammatory mechanism of dexamethasone is very complex but primarily it inhibits the activity of inflammatory cells and it suppresses the activity of inflammatory mediator the inflammatory mediator may include our chemicals that make our vessels permeable and dilate and this anti-inflammatory
Property of dexamethasone uses widely clinically it is used in a number of diseases which will be discussed in the next slide clinical uses of dexamethasone as i told you it relieves inflammation it relieves swelling heat redness pain so we can use it in acute inflammatory bowel disease or you can say intestinal disorder including including crohn’s disease
Ulcerative colitis we can use in certain types of arthritis like rheumatoid arthritis or we can use in those cases that having inflammation around tumors in bone spine and brain and we can use hexamethasone in swelling and allergic type reactions like allergic rhinitis transfusion allergic reactions allergic anaphylactic shock allergic anaphylactic shock that
Includes the symptoms of trouble breathing facial swelling heaves or nausea vomiting additionally as an immunosuppressive agent it is first line agent in acute rejection so we can use dexameter zone in cases of aplastic anemia immune thrombocytopenic purpura thrombotic thrombocytopenic popura hemolytic anemia and dexamethasone is one of the integral component
Of most immuno suppressive protocols for both induction and maintenance additionally we can use hexamethazone in certain types of cancer including leukemia lymphoma and multiple myeloma plus dexamethasone also used clinically in addison’s disease it is used to replace the steroids in condition of adrenal insufficiency means there is a low production of needed
Steroids produced by adrenal gland and last it used in po means post-operative nausea vomiting dexamethasone is one of the most commonly used antibiotic it acts on glucocorticoid receptor-rich bilateral nts nts means nucleus of solitary strength that is vomiting center we can use examine the soul for the profile axis of p o and b and it is safe and effective
Its iv dose is 5 to 10 milligram for adults and 0.15 to 1 milligram per kg for children can can be administered before or after the induction of anesthesia all right at the beginning of surgery but it has been noticed that it is more effective when given at the beginning whether than at the end of surgery now dexamethasone in the era of covet 19. if we talk about
Cobain 19 so dexamethasone is effective for those who are at high risk means who needs oxygen or mechanical ventilation dexamethasone doesn’t appear to help those who have milder symptoms it is beneficial for those who have breathing problems that require oxygen or ventilatory support and it reduces mortality in these type of cases according to the recovery trial
For coping 19 it has been shown that dexamethasone could reduce covet 19 patient debt risk by one third it has been evident that at the dose of six milligram once a day for up to 10 days it reduces 2018 mortality in patients receiving expiratory support now how dexamethasone works in covalent it works because it has targeting properties it has anti-swelling
Properties means it prevent fluid accumulation it has anti-fibrotic properties means it inhibits the accumulation of sky tissue it reduces fibrosis basically dexamethasone works by dampening down the body’s immune system chronovirus triggers inflammation as the body tries to fight it off but sometime what happens our immune system goes into overdrive called
Cytokine storm and it proves deadly because the body starts to attack their own cells so in kobe 19 due to cytokine storm inflammation of you that causes diffuse lung damage so what dexamethasone do it modulates inflammation that results in a lung damage or lung injury that reduces progression to respiratory failure and death now did you know guys long-term use
Of corticosteroid can cause osteoporosis diabetes and cataracts side effects the ugly side of dexamethasone but don’t worry the side effects depends upon the dose administered and duration of its use at high doses they cause side effects although it has favorable benefit risk profile the side effects are listed here including hyperglycemia means increase in blood
Sugar so the patient having diabetes may need to have blood sugar level monitored more closely and possible adjustment to diabetic medication must occur glaucoma and cataract fluid retention hypotension psychological effects weight gain increase risk of infection because dexamethasone dampening down the immune response so the patient may prone to infections and
The last one but not least osteoporosis means the thinning of the bones
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Dexamethasone pharmacology | Dexamethasone moa uses side effects | pharmacology of dexamethasone By excelsior medics