Jan 7, 2018
This one-day, two hour seven lecture series provides a basic understanding of how to recognize common drug names, understand the basic classifications, and quickly memorize them for exams. The print, e-book, and audiobooks these lectures are based on, Memorizing Pharmacology: A Relaxed Approach, can be found here https://www.amazon.com/Memorizing-Pharmacology-A-Relaxed-Approach/dp/B01FSR7XZO/
Welcome to the Pharmacy Leaders Podcast, with your host, Tony Guerra. The Pharmacy Leaders Podcast is a member of the Pharmacy Podcast Network. With interviews and advice on building your professional network, brand, and a purposeful second income from students, residents, and innovative professionals.
Welcome to Episode Four: Immune and Antibiotic Pharmacology.
Tony: Welcome to chapter four, immune. There's 40 some medications here, so I just wrote it up. I put one group out of order. My hand cramped from writing all of this, so I'll just tell you which one's out of order, but we'll get to that in a bit.
The first thing I want to do is I want to start with four OTC medications. OTC neomycin polymyxin B and bacitracin. This -mycin stem you may have seen before, it just means that it's from the streptomyces bacteria, but it doesn't necessarily tell you that it's exactly an antibacterial, but neomycin, polymyxin B, bacitracin, this is Neosporin. So, what we're going to do is we're going to go through antibacterials, antifungals, antivirals with these four medications in that order and then through the big list we're also going to go antibacterial, antifungal, antivirals.
So, the antifungal over-the-counter. You might know Lotrimin Ultra, we use for athlete's foot and things like that, it's butenafine. Then influenza vaccine, so again using the prophylactic, something that's trying to prevent infection before we use something acute, docosanol. So, influenza vaccine has one of its brand names as Fluzone and when you see flu in a brand name that means influenza, but if you see -flu- in the generic name, except for obviously the word influenza, like fluoxetine Prozac or another ones escaping me now, but that means a fluorine atom. So, be careful about using flu to mean for the flu or for influenza.
Docosanol, it's Abreva. I had no idea why anybody would pay 20 bucks for this, but it'll make your cold sore go away much faster, but think about docosanol so you can go to the ball or you can go to the prom, that's I guess why you would spend 20 bucks on something like that, but it abbreviates the amount of time that that cold sore lasts, so Abreva.
Let's start with the first antibiotic or antibacterial section. I had a little piece of tape here on the board, so we put penicillin over here, but we have one penicillin antibiotic, but something unusual about it. We start with amoxicillin, which is Amoxil, and this has the -cillin stem and so amoxicillin penicillin methicillin these are all penicillin antibiotics, we see that from the stem, but Amoxil is the brand name. You just took out the -ic- and then the -lin-, but what's this clavulanate?
So sometimes the bacteria can secrete an enzyme which can make the antibiotic ineffective. That beta lactamase enzyme can destroy the amoxicillin, but if you add this clavulanate you can augment, and you see that word augment in Augmentin the brand name, this amoxicillin. The cephalosporins are related to the penicillin’s they work on cell walls as well, so I'm not going to get too much into mechanism of action that's all in the book this is just review. The archaic one was C-E-P-H and I think they got rid of this because ceph- means brain or head if you're talking about medical terminology and its brand name is Keflex, but this is first generation.
What that means is that a first-generation drug has three properties that a third or fourth generation wouldn't or the other way around third and fourth have properties that first wouldn't. So, a third and fourth generation would increase gram-negative coverage would increase the ability to prevent beta lactamase attack, just like the clavulanate does with the amoxicillin, ceftriaxone and cefepime a third generation and fourth generation drug both do the same thing and then these two have better penetration into the cerebral spinal fluid if there's some kind of infection there, but again the stem is cef-, C-E-F.
So, the importance with putting vancomycin here when it doesn't seem to relate at all is that vancomycin also affects the cell wall. This -mycin stem again isn't really going to help you too much, but vancomycin is a glycopeptide and it works a little bit differently against methicillin-resistant Staph aureus something like that, but these are all grouped together.
This is where I kind of mixed it up. The tetracyclines should be before the macrolides, but you can see tetracyclines doxycycline from the c-y-c-l-i-n-e and minocycline from c-y-c-l-i-n-e. The reason they're called tetracyclines is because they have four rings, so the game Tetris was actually the Tetra for four and tennis. So, the person who invented it just combined those two together. So, we're just naming this class after the four rings in it. Then Doryx for doxycycline is the brand name and then minocycline's brand name is Minocin.
Then we have the macrolides. That macro- comes from just being a big molecule that's why they're named that way. This is an interesting one where we see the -mycin, but we also see something very similar in the middle the T-H-R-O and this might be an infix, I'm not exactly sure, but -thromycin you see that they all have that and that's one way to think that these three are macrolides. Now, do all macrolides have -thromycin? No, but this is a little bit helpful.
So, azithromycin is a z-pack. The way that I order it is that you only take that one once daily. Clarithromycin you take it twice daily so once daily then twice daily so Biaxin, twice daily. Then erythromycin is taken four times daily. So, the way that i put this in was to put it in number of doses a patient would have to take per day, one two and four all.
We're actually continuing on to the next with some other antibiotics Clindamycin which is Cleocin. You see this used a lot topically because it can cause some severe side effects severe diarrhea, so clindamycin a lot of times we'll see used for penicillin allergic patients and dentistry. The oxazolidinone linezolid and you can kind of see the classification in the name, the zolid stem again here puts it in that class, but Zyvox is very solid or 'zolid' against MRSA and vancomycin-resistant enterococci.
Amikacin and gentamicin both have those, the -kasin and -micin stems tell you the -micin doesn't tell you it's an aminoglycoside but these two are related in that way so Amikin and Garamycin. The two dihydrofolate reductase inhibitors. So, sulfa- and -prim are both a prefix sulfa- so let's you know it's a sulpha medication and trimethoprim the -prim lets you know that it's a dihydrofolate reductase inhibitor. What does that mean? Well bacteria need folic acid just like we do but they have to make their own, so if you block them from making their own it would kill the bacteria or hurt the bacteria. Then if you take a couple letters out of the word bacterium you get Bactrum, the brand name.
This fluoroquinolone is interesting because of the -oxacin suffix. So, the -oxacin is the suffix and then this -fl- is an infix and this fluorine atom makes it a fluoroquinolone rather than just a quinolone and then Cipro just got, you just cut off the -floxicin to make Cipro from ciprofloxacin and then Levaquin is like Levaquin except it's a quinolone, so the -quin for that. Antiprotozoal, metronidazole, so -nidazole is the stem and it's an amidazole antibiotic so you could see those letters kind of similar together and this is flagyl. TB, I use R-I-P-E as the acronym or way to remember it. When you think of that raised section that if you would have a positive in duration on a TB test I would think it's ripe like it's a welt or swelling. So, rifampin Rifadin isoniazid INH pyrazinamide PZA and ethambutol which is Myambutol.
There's clues in there that I mention in the book about how to remember what the side effects are for those, but again we're still in the antibacterials and with all these medications and now we're going to move over to the antifungals.
So, three antifungals. A lot of times students will try to be very efficient and they'll just try to remember the generic name, but amphotericin B doesn't really tell you much about what it does, but Fungizone own certainly tells you it's for fungus. Fluconazole the -conazole stem, some people get this wrong and they put that -azole stem in there and -azole- is just a zole, it's just an organic chemistry group. So, you don't want to use -azole because if you do that then you say fluconazole and omeprazole, a proton pump inhibitor in the same class and that's just not true. Nystatin, so this is Mycostatin so if you've had microbiology class you know the myco- means some kind of fungus.
Be careful with this -statin, so the -statin and nystatin, the -statin in Mycostatin there's a class of HMG-CoA reductase inhibitors that are anti-cholesterol medications that have this -statin stem and really the -vastatin is a better way to do that and I'll talk about that when we get to cardio.
Oseltamivir, so the -amivir is the stem here and these brand names are great, they tell you exactly what it's for. Oseltamivir you tame the flu, which is influenza and Zanamivir is Relenza make the influenza relent, so pretty good brand names there. Another antiviral for herpes simplex virus and varicella zoster virus - acyclovir. So, -cyclovir is the stem and this again I didn't mention this -vir stem but it's kind of a sub stem, so -vir is the all-encompassing antiviral stem but -amavir tells you it's for the influenza -cyclvir tells you it's for HSV and we have Zovirax, so zoster virus acts the zoster virus or wreak the virus. So, you can see the val- from Valtrex and val from valcyclovir are similar.
So, some similarities there I go over it all in the book.
Palivizumab, so again we have a monoclonal antibody, m-a-b and this is for respiratory syncytial virus. So, we've had a medication that's a biologic with this kind of naming for asthma for ulcerative colitis and as an antiviral, so this -mab doesn't tell you what it's for, but the -vizu- with the -mab helps you understand how it's working within the body. Then this is Synagis. So, those are the antifungals and then the non-HIV antivirals.
The next thing I’m going to do is go over the HIV antivirals. I haven't mentioned the top 200, there's going to be 200 drugs in this list. The top 200 drugs tend to omit the HIV medications, but I think it's essential that we talk about them and certainly how HIV works in the body. So, let’s go to the HIV medicines.
So, what I did was I put them in an order that makes sense in terms of how the HIV virus attacks the body. The first thing the HIV virus tries to do it tries to fuse, so we've got enfuvirtide and you can see the -fu- from fuse, but the -vir- stem and then the Fuseon, so something that's trying to fuse with the healthy cell. Then you've got miraviroc which is a CCR-5 antagonist, a cellular chemokine receptor antagonist and again we're still outside the cell trying to get in and if you look at the brand you see Selzentry. So, sans entry means no entry, so that's one way you can think of it that we don't want this virus to get in.
Efavirenz is a non-nucleoside reverse transcriptase inhibitor and it's paired here with emtricitabine and tonofovir. Which comes to Atripla so the trip, I have triplet daughters, but this triple makes three drugs in one medication and then the A surround it, so maybe against AIDS or something like that. Efavirenz is a non-nucleoside reverse transcriptase inhibitor, an NNRTI. Emtricitabine and tenofovir are nucleoside nucleotide reverse transcriptase inhibitors or NRTI. So, a mouthful certainly but hopefully a good way of remembering it that we're going from fusion and CCR5 antagonist outside the cell. Now this HIV virus is trying to attack reverse transcriptase and then it's going to try to attack integrase and then protease and so by stopping reverse transcriptase by stopping integrase by stopping protease we can hopefully stop the HIV.
So, we have raltegravir and this is Isentress, so again we see that century as the brand name and then Darunavir which also is Prezista, so we're resisting the HIV virus with a protease inhibitor. You kind of see the -tegrase T-E-G-R-A-V-I-R in raltegravir and darunavir, it's really the brand name with Prezista that you see the protease inhibitor.
But the key is that by memorizing these five brand names and then you certainly got the combination here so it's eight actual medicines but one two three four five six seven, seven actual medicines. Let me do that one again. So, by memorizing HIV medications and we have seven medications but five different types here the key is that we're learning how does HIV go from this to this to that to that and so these orders aren't just about memorizing it but also memorizing the pathophysiology that goes along with understanding HIV.
Male speaker: Support for this episode comes from the audio book, Memorizing Pharmacology: A relaxed approach. With over 9,000 sales in the United States, United Kingdom, and
Australia, it’s the go to resource to ease the pharmacology challenge. Available on Audible, iTunes, and Amazon.com in print, eBook, and audio book.
Thank you for listening to the Pharmacy Leaders Podcast, with your host, Tony Guerra. Be sure to share the show with a hashtag, #PharmacyLeaders.