This is a short video on drugs used to treat the obstructive airway disease asthma.
This is a short video on drugs that are used to treat asthma the obstructive airway disease before we begin we want to give a brief introduction to the pathogenesis of asthma as most ripley typically caused by a trigger such as an antigen irritant it could be stress it could be exercise it could be hypoxia there’s a whole list of triggers for asthma but either
Way these triggers are going to release some mediators that cause inflammation the inflammation involved with asthma involves proliferation and invasion of several white blood cells including lymphocytes eosinophils macrophages and mast cells there’s also a release of several mediators including ige il5 and leukotrienes now each of these are important in how
The drugs used to treat asthma work it’s important to their mechanism of action and we’re going to be talking about that so three of the main effects from asthma inflammation are sympathetic bronchospasm now this is mediated with the beta-2 adrenergic receptor there’s also a bunch of mucous secretion including vasodilation collagen deposition alveolar remodeling
Hyperplasia all this all phenotypic effects of asthma everything that happens to somebody with asthma during an attack and there’s something called reflex parasympathetic bronchospasm it’s not really understood how this works but the bronco bronchospasm causes the muscles around the airways to constrict causes them to tighten and it makes the symptoms worse it’s
A reflex parasympathetic and bronchospasm we’re going to be talking about how different drugs interfere with different parts of this pathway now this is the list of all the drugs whited out we’re going to be going through them one by one the main drug used for asthma rescue therapy this is when somebody’s having an asthma attack and they need quick acting results
Is a beta-2 agonist specifically a short-acting beta-2 agonist most commonly used is albuterol again this is used when somebody has an asthma attack they spray some albuterol down their throat and it really it relieves the sympathetic bronchospasm that’s associated with the inflammation that is that as a results from asthma now sympathetic or excuse me now beta-2
Agonists like albuterol cannot really be used long-term they lose their effectiveness over time the body begins to reduce the amount of receptors for these drugs so in order to have a long-term medication that we can use to treat asthma inflammation quite chronically we use long-acting beta agonists like cell material and foam at all combined with corticosteroids
It’s very important that these drugs be used together if the long-acting beta agonists are used alone they can have deleterious effects they can make asthma worse and haled corticosteroids are important with them they increase the prevalence of the beta-2 adrenergic receptors and inhaled corticosteroids are also important because they are inhaled we do not want the
Side-effects of systemic corticosteroids which include fat redistribution some emotional effects and and other side effects of chronic cordilla critical steroid use so always used inhaled corticosteroids and log acting beta-2 agonists together it’s possible to block leukotrienes that are involved in the asthma inflammation it’s easier to remember these drugs like
Montelukast because they all have lu or le eu in them just like the word leuco try now leukotrienes if you remember our results of a ragged nanak acid arachidonic acid can be catalyzed by either or locks one of the types of asthma is is induced by aspirin use which is an nsaid that blocks the cox enzyme and it causes asthma because it causes ragged onic acid to
Be catalyzed by locks into leukotrienes leukotriene blockers would resolve this kind of asthma and prevent inflammation as a result of leukotrienes released by the lipid mediators another drug we can use are phosphodiesterase inhibitors this includes caffeine and theophylline these block the mediators that cause the inflammation and they essentially allow for the
Build-up of cyclic anp cyclic afp has a couple roles in preventing inflammation it’s in the pathway for beta agonist activation so it allows the beta agonists to work a little better it’s it’s downstream in that g-protein pathway cyclic am p also has an effect on mast cells and it prevents degranulation of mast cells which also prevents inflammation a newer class
Of drugs for asthma treatment include monoclonal antibodies specifically o’malley zoom ab for anti ige effects and meppel ism ab for anti il5 effects now il5 stimulates the release of eosinophils granules it recruits eosinophils it allows them to release mediators like histamine so using methyl assume ab prevents eosinophils from contributing to the inflammation
Caused by asthma oh pollution map on the other hand is anti ige anti ige means that the mast cells will not will not be active this prevents the pathway involved with il-4 where where the b cells do class switching from igg to ige and if you administer oh melissa mab the ige will not be effective these two antibodies are relatively new but they’ve shown to have
Improved results in people with asthma and finally are the muscarinic antagonists now this class of drugs involves the reflex parasympathetic bronchospasm the bronchospasm that that contributes to many of the symptoms of asthma is activated by the parasympathetic nervous system the parasympathetic nervous system of course requires the use of acetylcholine to
Activate the cholinergic ad the cholinergic muscarinic receptors muscarinic receptors are at the end of the nerve terminals that activates the smooth muscles around the respiratory tract directly so these muscarinic antagonists such as a pro to opium or tiotropium block those muscarinic receptors and prevent the parasympathetic nervous system from causing the
Bronchospasms these are easy to remember because they all end with em and they all block the muscarinic antagonist muscarinic starts with an m and these drugs end with an m and they block the reflex parasympathetic bronchospasm that’s all the drugs that we have to treat asthma right now there are some new ones on the market but these are the main classes that
Are currently in use thanks for listening i hope this was helpful
Transcribed from video
Drugs for Asthma Treatment By MedLecturesMadeEasy
