Leukotriene Inhibitors | Montelukast, Zileuton

This video discusses Leukotriene Inhibitors.

Hello everyone and welcome to a little bush let’s take a new question a 22 year old female patient has mild asthma for which she uses inhelture acting beta to agonist for the attacks as well as daily inherit corticosteroids at present the symptoms are not controlled and she becomes severely out of breath whenever exercising he decided to add another drug for

Maintenance therapy which is the most appropriate drug group that will also prevent the patient’s symptoms during exercising a xanthine derivatives b chromoline c leukotriene antagonists and d anticholinergics in this video we will be talking about the class of leukotriene inhibitors so let’s get right into it before we get started we have discussed the arachronic

Acid pathway in which one of the metabolites is leukotriene in a previous video so it will be very helpful to revise that before starting this video and as a summary in the beginning we will have arachdonic acid paraclinic acid will be converted into leukotrienes and the main enzyme responsible for this reaction is called 5-life oxygenase then leukotrienes will

Go and bind to surface receptor glucotriene receptor and they will exert their effects like vasodilation chemotaxis edema formation and broco constriction and i want you to focus about the bronchoconstriction because it’s so severe that it is estimated to be thousand times more button than histamine imagine that so as the name suggests leukotrienes inhibitor

Will inhibit leukotriene thus reversing the broken constriction so the first drug that i want to talk about today is called xylitoine xylitoine inhibits the enzyme 5-lyboxogenes thus it will inhibit the production of leukotrienes other leukotriene inhibitors include mentallocast the ferulocast and brandlocast work by inhibiting the leukotriene receptor so

Let us make the names a bit easier to memorize if we can see all of these trucks have low in their names zelo toen montelo cast the fair low caste and brand low cast so this indicating that they are local triangles inhibitors another thing that you might have noticed already is that all the leukotrienes receptor antagonists have the suffix cast in their names

Montelio caste the ferlocas and brandocast so if there is law it’s allocating antagonist and if it’s low caste it’s locotrine receptor antagonists now to hammer this home let us discuss the worst question an examiner can give you the question state that which of the following drugs can reduce the effect of leukotrienes on that issue if you want more time you

Can pause for a few seconds and if you are ready i will break it down for you now we can directly eliminate the answer a and d aspirin and alpracedile because they we know that they are not related to leukotriene inhibitors but we still have montalucas and zeritoin which both work on the leukotriene pathway but if we can notice that it’s asking specifically

About the effect of leukotrienes and in this way the answer will be ontellocast because montolo cast work on the receptor thus inhibiting the effect of leukotrienes now let’s compare this nasty question with another one instead that which of the following drugs can reduce the levels of leukotriene in the tissue and the answer to this question will be zelitoen

Because it’s asking about the levels the little one inhibits the enzyme 5-life oxygenase thus we will have less glucotriens in the tissue so again it’s the same question but there is only one word different in it so montello cast acts on the receptor thus reducing the effect or action of leukotrienes the little end on the other hand acts on the enzymes which

Make leukotrienes thus it will reduce the level and the concentration of leukotriene let’s move now one step further and talk about the side effects of this drug first for the little one it’s a hepatotoxic drug so you should follow up the liver function tests and neuropsychiatric reaction which i will be talking about it in just a second and for leukotriene

Receptor antagonists we have gi disturbance like nausea vomiting and we have no psychiatric reaction now let us discuss the neuropsychiatric reactions associated with leukotriene inhibitors in 2019 and 2020 neuropsychiatric reactions were added to the label in the uk and the usa these neuropsychiatric reactions includes nightmare depression hallucination suicidal

Ideations agitation and anger and lastly insomnia which is the inability to sleep the reactions were mostly noted with montello caste and even the fda have proposed that the drug on telecast require a boxed warning aka the agency most prominent warning to be added because most of the healthcare workers are still not aware of how serious these neuropsychotic

Reactions can be so the main takeaway of this slide know that leukotriene inhibitors and specially montalocast are associated with serious neuropsychiatric reactions know it for your patients and know it because it might be a potential question in future licensing exams now lastly let’s finish up by talking about the medical use of leukotrienes inhibitors first

They are used in aspirin-induced asthma and exercise-induced asthma and breathing sleep disorder in children and allergic rhinitis and hives for the last two condition the sleeping disorder and allergic rhinitis now nowadays it’s less used because of the neuropsychiatric reactions so let me explain why they are very effective in aspirin and exercise induced

Asthma so this diagram is from our previous video on arachtonic acid pathway now how aspirin induced asthma and how leukotriene inhibitors work effectively in this situation so aspirin will work on cox-1 and cox-2 enzyme thus inhibiting all the right arm of this pathway so whenever our body produces arachnonic acid it will be all shifted to the left side to

The leukotriene pathway thus we will have more leukotriene and more leukotriene will result in bronchoconstriction so the leukotrienes inhibitors will be very effective in this year’s second for exercise induced asthma we know that exercise will stimulate the phospholipase a2 so that will give us more arachidonic acid and more organic acid will give us more product

Of its pathway including the leukotrienes in the same way more leukotrienes we will have bronchoconstriction and the drugs will inhibit this thing lastly let us answer the question that we give in the introduction of this video so after a long scenario as they usually give us the main key as i highlighted over here is that it’s asking about the most important

Drug group that will also prevent the patient’s symptoms during exercising and the answer to this question is c leukotriene antagonists in the end thank you for watching and see you in another video

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Leukotriene Inhibitors | Montelukast, Zileuton By A Little Push