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PHARMACOLOGY- ANTI TB MEDS

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A user-friendly quick and hi-yield guide to the must-know pearls about Anti-Tuberculosis medications

Hello this is doctor and welcome to the med guru cbb channel we’re gonna have a very comprehensive short discussion about the medications used to treat tuberculosis so this is the anti-tuberculosis medications so tuberculosis as you know is caused by mycobacterium tuberculosis and this is common in developing countries such as the philippines now i want everyone

To memorize this the common drugs used for tuberculosis your mnemonics here is stripe so we have streptomycin rifampicin isoniazid tyrosine amide and ethambutol so these are the common most common drugs use for the treatment of tuberculosis so again stripe now this is the sequence which we follow in the dlh the department of health the world health organization

And treatment for our patients with pulmonary tuberculosis we have the famous acronym h r ze and we have the drug after the hr ze regimen we have the s which is streptomycin so the h stands for isoniazid the r stands for rifampicin and refampin z stands for tyrosine amide he stands for exampie at all s stands for streptomycin now always remember this all of your

First-line anti tb mets are bactericidal except i will repeat x you’re ethambutol your first line anti tb meds are all bactericidal except here if a butyl which is bacteriostatic now here is an illustration take time pausing the video going over this take notes so our first line drugs all of them are oral except for streptomycin which is intravenous the second

Line drugs just to mention a few sigh closer in i mean casing caprio my scene and we’re gonna end up discussion this discussion mentioning the novel generation of anti-tb drugs don’t worry i’m gonna dissect this diagram so let’s start with the first line drugs isoniazid rifampicin if ambit all pyrazine amide all of them are oral it is only streptomycin which

Is intravenous now what about your second line these are the ones i want you to memorize if i own amide cyclo serine i added fluoroquinolones then you have your amino glycosides namely amikacin kanna my scene and caprio my scene don’t forget the amino glycosides they are given intravenous and of course your novel generation anti-tb drugs we have 3 de la moneda

Predominate and bataclan de la moneda predominate and the baculum now let’s start with isil thigh is a diverse the exact mechanism of action of iso knives a the one which is stated in most references is the inhibition of mycolic acid don’t forget my colleague acid is a very important component of the bacterial cell wall of your micro bacterium so i so now is it

Inhibits mycolic acid and isoniazid also has a secondary mechanism and that is eysan eysan has the enzyme desaturates so let me rephrase i so nice it inhibits the enzyme desaturates rather than it has the enzymes i stand corrected i so now is it inhibits the enzyme desaturates and this enzyme desaturates is involved in the cell wall synthesis of your bacilli your

Mycobacterium the c line now what about toxicities or side effects so just remember this mnemonics i and h so number one i so now is it causes accumulation of iron in the mitochondria and this leads to sinner aplastic anemia i so now is it is notorious for causing neuropathy or neuritis because isoniazid impairs the absorption of vitamin b6 or pyridoxine ionize it is

Also hepatotoxic and can also cause hepatitis now let’s play around and please let me know what do we call this syndrome arthritis rash photosensitivity fever myalgia after intake of a truck this is your famous drug-induced lupus so drug-induced lupus or lupus like syndrome is characterized by arthritis rash photosensitivity fever and myalgia and drug-induced lupus

Is associated with your anti histone antibodies so drug-induced lupus is associated with your anti histone antibodies now bring this with you to your exams the mnemonics for drug-induced lupus hip hop emcees so hip-hop mcs so we have the following drugs hydralazine i so now is it procainamide phenytoin oxcarbazepine pro passive propafenone minocycline carbamazepine

And sulfonamides so hydralazine isoniazid procainamide phenytoin oxcarbazepine profit propafenone minocycline you might want to add another letter in there that’s methyl dopa carbamazepine and sulfonamides so hip-pop mcs now what about rifampicin now the mechanism of action of rifampicin just remember letter r is letter r for rna polymerase rifampicin binds with

Rna polymerase thereby inhibiting rna or protein synthesis now to be specific reef amp is een will bind to the better subunit of your rna polymerase thereby inhibiting rna or protein synthesis side effect or if an kassim is famous for causing red orange body fluids it makes your sweat your urine appear red orange so recon bussiness letter r that means it revs up

The rna polymerase and letter are red orange body fluids what about it then butyl the exact mechanism of myth if a butyl is inhibition of the enzyme micro bacterial are a be no sill transferees so your arabi no cell transfer is inhibition leads the inhibition of araby no glycan now what is the significance of this i rubino glycan i rubino glycan is important for

The bacilli cell wall synthesis now what’s the usual dose of the tablet all memorize the magic number 15 mix per kilogram per day so 15 milligrams per kilogram per day side effect of ethambutol is the famous retro bullbar optic neuritis and decrease in your visual equity so always remember this retro bulb our optic neuritis or decrease in visual equity okay also

Presents with this description the barrel vision or the red orange blindness so the first manifestation you’re going to get with a fabulosity is actually going to be loss of your color vision and this is dose dependent so what are these doses so the recommended dose is 15 mix per kilogram per day optic neuropathy occurs in about 1% as you increase the dose 25

Mix the risk is now 5% and with a high dose of 50 milligrams the risks of the optic neuropathy or the optic neuritis now increases to 15% so one of the first things you’re gonna be asked is what will you do if a patient presents with loss of color vision or loss or decrease in visual equity and the patient is being treated with ethambutol first discontinue the

Drug and recovery usually occurs after discontinuation of the drug and it is rarely permanent so what about pyrazine amide the exact mechanism of pyrazine amide is it will inhibit the enzyme tyrosine amenities so pyrazine amide acts on pyrrha xena middays now this pca days is responsible for the deamination of pca to pyrazine oeq acid so pyrazine a zener many

Days the ammonites the pyrazine amide to piracy noack acid which is also known as your poa now if you look at this illustration tyrosine amide this is a nicotinamide analog pyrazine amide okay so this is the enzyme here tyrosine intimidates or your nikitina nikitina middays this will ack on your enzyme thereby converting pyrazine amide to pyrazine oeq acid and

This is responsible for the killing of the mycobacteria now for the toxicity please memorize pyrazine amide it’s notorious for causing hyperuricemia and this is also associated with hepatotoxicity now streptomycin is an aminoglycoside and mechanism of action as an aminoglycoside as it binds to the 30s subunit so please memorize by heart your 30s subunit okay so

Please memorize your 30s subunit and thereby causing inhibition of your protein synthesis so memorize the 30s subunit and if you inhibit 30s subunit you will inhibit protein synthesis so don’t forget streptomycin which is an aminoglycoside binds to your 30s subunit thereby inhibiting protein synthesis and just like all of your amino glycosides don’t forget the

Two toxicities you have to bring with you to the exam and to your clinical practice number one is nephrotoxicity number two is auto toxicity so streptomycin is associated with ototoxicity and nephrotoxicity and don’t forget of your first line anti-tb drugs your streptomycin is what is absolutely contraindicated in pregnancy because it can cause congenital deafness

Now here take time to go over this the usual side effects major side effects that come out in exams for your first line anti-tb drugs so don’t forget rights r.i.p es that’s rifampicin if i so know is it pca then you have in hand at all and streptomycin rifampicin causes the red-orange secretions into red orange urine ice on eyes it causes the peripheral nervous

Tyrosine amide causes increase in uric acid if a mute all causes the visual problems streptomycin is auto toxic so let’s wind up this talk regarding the anti tb meds i’ll just mention in passing your novel generation anti tb meds so you have dilemma need this is derived from the nitro dihedral imidazole boxes all class oh that’s a tongue twister nitro dihedral

Imidazole oxes all class of compounds that inhibit mycolic acid synthesis your dilemma need according to the cdc and whu-oh is reserved only for the treatment of multi drug-resistant tuberculosis and extensively drug-resistant tb so that’s delaminate now winding up the daca lien is also reserved for multi drug-resistant tb so the novel generations of anti tb meds

Are reserved for mdr tb an extensive multi drug-resistant tb so mechanism of action by jacqueline it inhibits the mycobacterial atp synthase so this is the enzyme which uses energy of protons flowing across the cytoplasmic membrane in order to synthesize atp so big a killeen inhibits mycobacterial adenosine triphosphate synthase take time to go over this video

Again make sure you master the pearls highlighted here these are important for exams these are important for your clinical practice so this is doctor saying thank you god bless and please continue supporting watching our videos and subscribing to the med gurus cdp youtube channel thank you

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PHARMACOLOGY- ANTI TB MEDS By Med Guru CDB