MYCOLOGY MCQs

today we'll be covering antifungal drugs for pharmacology this is not only important from the neuropharmacology but also important from you of oral pathology and oral medicine men also clinically where we prescribe antifungal agents for various anti fungal infections which are the potential ncq topics for the niche preparation so here I will be covering the brief concepts of how antifungal drugs act and the important points of the various antifungal drugs so to know how the antifungal drugs would act first of all we need to be clarified about how the fungal cell is made up of right so the most potential part and the resistance part of the fungal cells has is the cell wall and cell membrane right so a cell wall it is basically made up of chitin which is nothing but a long chain amino acid that is n acetyl glucosamine and the carbohydrate sugar that is glucans that is the most familiar beta chain glucans that is so beta 1 6 and beta 1 3 type some of them also have alpha type that is 1 for alpha glucans and they are made up of proteins that is most probably in the form of nano proteins now coming up to the cell membrane the cell membrane of fungal cell is made up of Agua sterile unlike in human which is made up of cholesterol right so uh and the drug would be acting and the process of DNA synthesis or the synthesis of proteins and acting upon the fungal cell and now how the fungal cell would be attacking right so basically whenever we are planning for our attack what we'll do we plan right how to attack from the entry and how to be make the three weeks right so similarly this Drugs Act they act on cell wall they act on cell membrane right they act on the component which is helping the formation of cell membrane right and then creating pores and inhibiting the cell division and inhibiting the protein synthesis right so now we have the drugs which are acting upon the cell wall these are basically in eco Mason's nekoma isn't they inhibit the chitin synthesis right then we have Aquino Canada that is cash performed in drug which specifically acts on one three beta glucan and they inhibit the component that is making up the cell wall right so we are inhibiting the components which are making of the cell wall so we are inhibiting the cell wall formation next coming up to the cell membrane right so we have alga steroids which is the component of cell membrane so now we would be acting upon inhibition of the say or go sterile formation so now how is a busted all formed right so we have sanguillen which in the presence of sanguillen epoxide would be converting into lanosterol and lanosterol which would be in presence of p450 14 alpha the time methylase would be converting into a ghost air alright so we have drugs which would be changing the membrane permeability by inhibiting the formation of lanosterol and alga stable so we have turbine afine which would be inhibiting the or bacillus inductance by acting upon sand filling epoxide and we have a salt group of drugs which would be acting upon 14 alpha d mentalize and inhibiting the conversion of lands to all - or question all right now what a go to release form so how we will inhibit tag and once the cell membrane is PO on how we would be acting upon it so we have fortress in B what does impression B does it binds with the ergosterol and forms the artificial fungal pores right the cell polls are mean so what when the pore formation is occurred there would be the cell content would be leaking out of the cell and else's contents leak out that would be reading verses that right and importance in B is the widest antifungal drug we have the spectrum right now there are microtubules in our cell as we know what - my two Liberals - they are helpful in spindle formation during the cell division so what we would be doing they're mostly present in microtubules are there in dermatophyte so we have grease or fuel means we which will be inhibiting this microtubule formation so as a result what we are inhibiting we are inhibiting the cell division of fungal cell in this way and inhibiting the process of cell synthesis so from all and we now have that is protein synthesis one of the most important aspects in the formation of cell wall right so how it would be inhibiting this protein synthesis that would be through gnosis cytosin file that is 5 FC this pi LC in the presence of enzyme / - can enter into the cell this file FC would be converting into 5 fluoro uracil in the presence of enzyme cytosine deaminase right so this a five-floor unison 10 would be converting into 5 Rolo deoxy you read o then mono phosphate right and then in the presence of time we delayed synthetase would be converted into deoxy time' dilates mono phosphate and help in the synthesis of DNA which would be further leading to the synthesis of protein synthesis so this drug is acting on the inhibition of time' dilation touches us inhibiting the DNA sequence formation and inhibiting the protein synthesis right so what did in a brief we have the drug which would be acting on cell wall drugs it would be acting on altering the membrane permeability drugs which would be inhibiting microtubule formation and drugs that are inhibiting nucleic acid synthesis right so now coming up to the classification so as we got to know how and where they are acting upon now we can easily classify it so inhibiting cell wall synthesis so which drugs would be there remember back entry cell wall that is aquino pendant that is tazbo found in group and lick amide sin which inhibits the chitin synthesis now this case for funding is a group in also a group of drug that is the new a group of antifungal drugs we have that is aquino candidates and they are mostly used intravenously and other drugs which are included in this group are Micah funding and any Dula fungal right then we have drugs which will alter membrane permeability so which were those number one we had terbinafine which was inhibiting the sample information to lannister your formation that is all this group of drugs turban arson lootin ofin and nasty fine this are our ghost eros plus lanosterol inhibiting drugs then we have and we assault inhibit the conversion of Leno's children into our children there are based upon this structure we have two types that is try as all then which are having three nitrogen group of structure and Amy - all right so try as nas includes new corners wall a truck a nozzle Waurika nozzle and pitaka nozzle right and we have imidazoles which include key token as also f IV p whip right FIV P is a try as all and kcb right it is a sceeto cañazo clotrimazole and blue token at all which are the in need as all group of your Mak CB and tries v EP right this see there you can remember then we have a poor liens group of drugs that is invert present be in the starting and hem Ison that is s am bicy il-10 my sync group of drugs then we have our drugs which would be disrupting microtubule formation that is the grease of whole beam and we saw poison is one of the system in drugs which we use for superficial skin infections and then we have block strug's which mill in EB nucleic sill acid synthesis that is sluices Towson's that is 5fc now here we have per second as all which is the only drug which will be acting against mucormycosis this is an important point to remember further we are also going for the other drugs and important factors of them now coming into the important points of various drugs that is we have number one we have fluconazole you know one of the most common drug we prescribe as an antifungal so Lucan as well is a drug of choice for candidiasis cryptococcal meningitis and it is used for prophylaxis prophylaxis of we brian neutropenia right fluconazole is for prophylaxis and what for the treatment of fervid value 2 ponyo so drug of choice for the treatment of supply neutropenia is very connoisseur clear about it now we have a track on assault a trap on us all is a drug of choice for blastomycosis histoplasmosis hokkaido mycosis and Perico koi de microcells and we have the another group that is a ketoconazole it is also having it inhibits the cytochrome p450 enzyme reaction right so it is important by the point of aspect of drug interaction because as we inhibit there are drugs which increase the p50 enzymes and there are drugs we decrease the p50 enzymes right p450 enzymes so we know that the drug interaction would vary that would be synergistic effect or an inhibitory factor other drugs so if skit of a nozzle important and difficult drug from the point of view if to be prescribed with other drugs right this would be we'll be covering it in later on now we have a newer group of drugs as we said cash flow function which would which where does it act 1 3 beta glucans right so this are the only approved drug and this will be used only in the cases where invasive aspergillosis is not responding to the oricon as one on amphotericin B right clear about it now coming up to war upon us all Molly Connors all is used for D or C of the brain neutropenia and also it is a drug of choice for invasive aspergillosis aspergillosis right clear up till now and now we have some of the topical drugs which are used so these are white fields or internment who knows you might be asked what is the composition of miles fins or invent so you need to remember it is basically benzoic acid with salicylic acid which is topical antifungal drug then we have Pauline group nest at in which is used for oral candidiasis and if it is a topically for oral candidiasis and nicotine is given orally for gastrointestinal fungi clear so you would be confused if it is oral candidiasis it is topical if it is guess kinda status unless then statin is given orally that is systematically systemically clear about it keep a note on this point that we have Tyler state and untie clinic acid and omit as well ketoconazole zu tokenizer all these are the L salts which are used as a topical are now coming up to a most important that that is info Terrace in B it is having a wider spectrum of antibiotic and it is useful as a coin friction for systemic fungal infections and it binds to ergosterol as we see it forms artificial pores and inhibit some create the spores and leads to cell death right so now what is the disadvantages of amphotericin B and it leads to those limiting nephrotoxicity and it can lead to acute infusion related reactions hypophosphatemia anemia and hepatic dysfunction right there are lipid formulations available for Mpho ter S&B there are amphotericin B lipid complex and pateros in B colloidal dispersions complex and liposomal amphotericin B right now what is the advantage of this lipid formulations of n fo Terrace in me these are that it leads to my your acute reactions can be used in intolerance to conversion of preparations have Lola fro toxicity L anemia and deliverer of amphotericin B to re s of liver spleen is so useful in Leishmania and immuno compromised to patients and it can be given in the higher doses right this is the advantages of lipid formulations of em Pateros in B now coming up to the interaction as I said that we have ketoconazole that inhibits the cytochrome p450 enzyme right so as this occurs cyclosporine phenytoin called glutamine this serum concentration increases right so ketoconazole is basically to be contraindicated with info Terezin B we must not give in the combination of info terracing be as it is inhibiting the action of amphotericin B now coming up to a combination of M fertilizing be with flu sisters's right so both this plugged when given together it occurs gives a spinner for synergism right so how it is advantageous that is entry of five neuro flu sisters and it produces that oxygen there is a rapid culture conversion reduction in duration of therapy and decreased resistance right so this is the advantages of flu sisters in and in photo recent the are leads to cynicism when given together and verify body Kaunas all the adverse effect of re canals all is that it prolonged QT interval and it has it causes a visual disturbances and that is called blurred vision altered color pearl perception and photophobia and as we discussed previously posture Kaunas all is the only as all that is active against Nucor mycosis so to be in brief we have a for blastomycosis we have a track on as well Nucor mycosis me up osaka nozzle candidiasis cryptococcal meningitis so we have flu kana do kana do ah as a prophylaxis for the brand new top anemia fluconazole it meant for pre-planned neutropenia we have worried Kaunas all as a drug of choice for invasive aspergillosis we have reconnaissance when it is not responding to very Kaunas all the drug of choice for invasive aspergillosis is kasper funding and we have a most wide spectrum of an antifungal that is info Terezin be for systemic drugs for superficial fungal infections we have grease or full wean aneil our minds that is terbinafine nasty fin and mutant ofin which are an assault that is ketoconazole fluconazole and itraconazole are used orally as systemic drugs for superficial infections and that's it for antifungal drug thank you thanks a lot for watching the video