December 8, 2022

Good morning this is me nafisa and today we’ll be learning about levocitazine and montulocast combination in allergic rhinitis allergy is body’s exaggerated response to an otherwise harmless substance there are four types of hypersensitivity reactions today we’ll be learning about type 1 hypersensitivity reactions only all of us at some point of time have suffered

From one of these redness of eyes itching of eyes watering of eyes sneezing running nose nasal congestion redness or itching of skin these are the examples of type 1 hypersensitivity reactions in order to understand what happens in an allergic individual first let’s understand what happens in a normal individual a body’s police that has white blood cells will

Identify any harmful substance or foreign substance entering a body this foreign substance or harmful substance entering the body is called as antigen examples of antigens are substances usually proteins on the surface of viruses fungi protozoa bacteria or non-living substances such as bacterial toxins chemicals drugs can also be antigens when antigen enters

The body then wbcs in our body tries to protect us from these antigens by producing antibodies antibodies is also called as immunoglobulins the type of antibodies produced is igm which is one of the first antibodies produced to fight infection later igg takes over these antibodies produced can neutralize or destroy the foreign substances or harmful pathogens or

Antigens that has entered the body and hence we are protected or can i say that we are healthy that is we do not suffer from diseases or infections does allergy happen to everyone no allergy does not happen when a person’s body identifies what is a harmful substance and what is a harmless substance but an allergic individual’s immune system cannot recognize harmful

Or harmless substances harmless substances to which allergic individual produces antibodies are referred to as allergens an allergen is an antigen but not all antigens are allergens most common examples of allergens are house dust mites animal dander moles these cause year-round allergy or what is known as perennial allergy grass pollens cause seasonal allergy

Medications or drugs like nacids or some antibiotics cause drug allergy certain foods like ground nuts eggs fish brinjal cause food allergy others example insect bites perfumes chalk powder etc when allergen or the harmless substance example chalk powder is inhaled since an allergic individual cannot recognize harmful or harmless substances so to these harmless

Substances also their body secretes excess antibodies antibodies secreted in an allergic individual are of ige class some of these ige antibodies will neutralize the allergen and as excess ige antibodies are produced so the other ige antibodies will bind on the surface of mast cells or on the surface of basophils thus mast cells and basophils are sensitized to

The allergen this is called as sensitization stage sensitization stage does not cause any symptoms when this allergic individual after some days or some weeks or some months is exposed to the same allergen for the second time allergen will cross link with the ige on the surfaces of mast cell signaling the mast cell or i can say it as activating the mast cell to

Degranulate degranulate means releases inflammatory mediators which are also called as inflammatory chemicals that is degranulation of mast cells takes place degranulation of mast cells takes place which releases many preformed inflammatory mediators inflammatory mediator most commonly seen an allergic individual is histamine in an allergic individual on second

Exposure or subsequent exposure to the same allergen degranulation of mast cell takes place and mast cell releases many preformed chemical mediators mediators means help as these chemical substances help in inflammation therefore these chemical mediators are also called as inflammatory mediators many preformed inflammatory mediators are released but the most

Important preformed inflammatory mediator is histamine this histamine on its own cannot show action that is histamine has to bind to histamine receptor to show its effects histamine receptors present in eyes nose skin and bronchi are called as h1 receptors if histamine binds to h1 receptors in eyes symptoms are redness of eyes itching of eyes and watering of

Eyes indication is allergic conjunctivitis if histamine binds to h1 receptors and nose symptoms are sneezing redness of nose itching in nose and rhinorrhea that is runny nose indication is allergic rhinitis rhino in medicine means nose rhea means excessive discharge so rhinoria is watering from the nose or runny nose rhinitis is again made up of two words rhino

Plus itis itis means inflammation rhino means nose so rhinitis means inflammation of the nose if histamine binds to h1 receptors in skin symptoms are little swelling or raised portion on the skin an indication is known as allergic dermatitis if histamine binds to h1 receptors in bronchi symptoms are difficulty in breathing an indication is allergic asthma these

Symptoms occur in seconds to minutes of second exposure to allergen therefore this process is called as early phase of allergic reaction this is also known as an immediate hypersensitivity reaction we need to remember the most important preformed inflammatory mediator released because of mast cell degranulation is histamine and this histamine is responsible for

The symptoms of early phase eight phase of allergic reaction occurs about four to six hours on second exposure or subsequent exposure to allergen and involves newly synthesized inflammatory mediators these new mediators are generated by breakdown of mast cells the membrane of the mast cell is made up of phospholipids and because of the breakdown of mast cells

The enzyme phospholipase a2 is activated and phospholipase a2 converts phospholipids to arachidonic acid and from arachidonic acid numerous leukotrienes and prostaglandins are produced how are they produced arachidonic acid is converted to prostaglandins by cox enzymes and arachidonic acid is converted to leukotrienes by lip oxygenase enzyme which uses flap

Paf also known as platolet activating factor is also a newly synthesized inflammatory mediator released by mast cells degranulation of mast cells also releases newly synthesized inflammatory mediators like prostaglandins leukotrienes and path leukotrienes is most important why is leukotriene most important because leukotriene is 100 to 10 000 times more potent

Bronchoconstrictor than histamine therefore leukotriene will amplify the action of histamine inflammative mediators causes these effects of redness warmth pain swelling these are the signs of inflammation all these inflammatory mediators are responsible for inflammation other effects of these inflammatory mediators are increased bronchoconstriction and mucous

Hypersecretion this occurs after four to six hours of second exposure to the same allergen and is called as late phase of allergic reaction late phase symptoms can be more severe than symptoms in the early phase when histamine binds to h1 receptors present on the eyes this leads to early phase symptoms which occurs within seconds to minutes these symptoms are

Redness of eyes itching of ice and watering of eyes the late phase symptoms are which occurs after four to six hours of second exposure of the allergen is more redness and swelling this allergic condition of the eye is known as allergic conjunctivitis when histamine binds to h1 receptors present on the nose the early phase symptoms which occurs within seconds

To minutes is sneezing redness of nose itching in the nose and watering of the nose that is rhinorrhea late face symptoms that occurs four to six hours is nasal congestion allergic condition of the nose is known as allergic rhinitis when histamine binds to h1 receptors on the skin leads to slightly raised elevation on the skin known as urticaria or wheel these

Are the early phase symptoms which occurs within seconds to minutes and after some time there is diffused redness or erythema or flare these are the late phase symptoms which occurs after four to six hours of second exposure of the allergen this allergic condition of the skin is known as allergic dermatitis histamine binds to h1 receptors on the bronchi leads to

Bronchoconstriction which is an early phase symptom and congestion of bronchial mucosa which is a late phase symptom this allergic condition of the bronchi is called as allergic asthma an allergic individual may have one or more of these allergic conditions as one is related to another for example when we have runny nose we may also have redness of eyes or watering

Of eyes and difficulty in breathing late face symptoms are because of inflammatory mediators like prostaglandins leukotrienes and peff glucotrine is however the most important inflammatory mediator responsible for allergic rhinitis and allergic asthma when leukotriene binds to leukotriene receptors leads to late phase symptoms of allergic rhinitis and allergic

Asthma allergic inflammation of the inner lining of the nose is referred to as allergic rhinitis early phase symptoms of allergic rhinitis are sneezing redness of nose itching in the nose and watering of the nose that is rhinorrhea late face symptoms of allergic rhinitis are nasal congestion episodic rhinorrhea sneezing obstruction of the nasal passages with

Itching of the conjunctiva nasal mucosa and oropharynx that is itching in the throat these are the hallmarks of allergic rhinitis chronic allergic rhinitis may be associated with sinusitis and otitis media symptoms generally appear before the fourth decade of life and tend to diminish gradually with aging although complete spontaneous remissions are uncommon that

Means allergy should be resolved after four to six hours but why is it that allergy symptoms are continued for days together at mediators also results in increased vascular permeability hence inflammatory cells like neutrophils basophils eosinophils leave the blood vessel and enter the site of allergen these inflammatory cells will release inflammatory mediators

And hence more inflammatory cells moreover each of these inflammatory mediator is a chemo attractant for eoxinophils so more inflammatory cells in the affected area eosinophils is a type of wbc that releases toxic substances that damages the invading cell and nearby host cells that is damages the epithelial cells so when the cells are damaged more inflammatory

Mediators are released if more inflammatory mediators are released so more inflammatory cells will come to that place and hence results in more inflammation this results in cascade of allergic reaction which leads to continuous symptoms at times even in the absence of the allergen euxonophils are the predominant cells in allergic conditions and asthma increased

Numbers of eosinophils in the tissues is a hallmark or characteristic feature of allergic diseases this explains why blood levels of eosinophils are commonly elevated in people with asthma and in other allergic diseases talking specifically about allergic rhinitis and allergic asthma histamine is important preformed inflammatory mediator histamine when it binds

To h1 receptors of the nose causes symptoms like sneezing redness of nose itching in nose and watering of nose that is rhinolia histamine when it binds to h1 receptors of the bronchi causes symptoms like bronchoconstriction these are early phase symptoms which occurs within seconds to minutes of second exposure to the allergen glucotime is an important newly

Synthesized inflammatory mediator leukotriene on its own cannot show any action leukotine has to bind to its receptors so leukotriene when it binds to cysteine leukotriene one receptors causes late face symptoms in the nose like nasal congestion and late face symptoms in the bronchi like bronchial congestion which occurs after four to six hours of second exposure

To the allergen it’s important to take care of early phase symptoms and late phase symptoms in order to stop early phase symptoms block histamine from binding to histamine receptors by giving a h1 receptor blocker example of which is levocitizine to stop late phase symptoms block glucotrines from binding to the leukotriene receptor by giving leukotriene receptor

Blocker like montilucast we need to give a combination of levocitizine and montulucast so that both early phase symptoms and late phase symptoms are taken care of combining levocitizine and montelukast gives additional benefits in comparison with either drug alone combination therapy of levocitizine and montulucast gives relief from nasal congestion a symptom

With a considerable impact on quality of life combination therapy with levocitizine and montulicast may have a positive impact on perennial allergic rhinitis and improved quality of life and also provides relief from nighttime symptoms thank you so much

Transcribed from video
Levocetirizine & Montelukast Combination in Allergic Rhinitis 9thNov2020 By Nafisa Harianawala